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We don't want to abandon our anchor or the midpoint.  And we want to keep a spare on the  6pt.  That narrows the choices somewhat to:
 

The aggressive 8/4*,
the passive 24/20,
and the moderate, thematic 15/11.

Any time you can put two men on the roof, you should take a good look at it, but I don't see the risk being worth the reward.  We're ahead in the pipcount and have fewer men back, so hyper-aggressive play is not called for.

But 24/20 is to passive, and the man on the 24 might be useful in holding rkb if things go poorly for us.

15/11 gets a checker out of harm's way (rkb will have to abandon the anchor to hit it) and brings in a builder.  With men on the bar we should bring in buliders to make home board points.  Seems like the right balance here.

15/11

This is getting lot harder then I thought. No hit is thematic but things have changed. If we make the loose hit and followed with dance we can cash and win immediatly. That's a big opportunity. If rkb doesn't hit back we will get nice double with quite many gammons and we really need those gammons in this score. So especially in this score and cube position I would do the loose hit. If the score were even I would be a lot more unsure about it and propably wouldn't have guts to do it. But here 8/4*. Let's go for it.

tempo 8/4*

I am liking the aggressive too, I know most will find that shocking  ;)

Hit. If we don't hit, and he comes back in on the 4, that's going to make for a very effective backgame and he's going to be harder to evict than cockroaches in a South Bronx apartment. We have 3 points covered already, so more dancing or bad situations for rkb is a definite possibility, in which case we cube. If he comes back in on a 4, it's not a major problem as we are already pointed on the 20. This is why I was initially in favor of cubing before the roll, as this is the kind of play that can turn into 4 points quickly. (Of course, this can blow up in your face from time to time as well)

Hit!  For all the reasons above!

Well done Forum! 8/4* is clearly best, probably even at a normal score, and much more so at this matchscore as it is clearly more gammonish. I wimped out with 15/11, I guess I had not properly reckoned with the fact that hitting puts the second checker on the bar, which is pretty strong given our three point board. It reduces the risk normally involved with breaking your eightpoint (the only outfield point we have) and hitting loose. Another factor is that the alternatives moves just aren't very good.

Big surprise here.

Evaluation says the hitting play is clearly superior:
    1. Cubeful 2-ply    8/4*                         MWC:  53.16%
       0.573 0.235 0.007 - 0.427 0.101 0.004
        2-ply cubeful prune [world class]
    2. Cubeful 2-ply    24/21 15/14                  MWC:  52.70% ( -0.46%)
       0.575 0.195 0.005 - 0.425 0.089 0.002
        2-ply cubeful prune [world class]
    3. Cubeful 2-ply    15/11                        MWC:  52.63% ( -0.53%)
       0.568 0.202 0.006 - 0.432 0.091 0.002
        2-ply cubeful prune [world class]
    4. Cubeful 2-ply    24/20                        MWC:  52.53% ( -0.63%)
       0.572 0.187 0.005 - 0.428 0.090 0.002
        2-ply cubeful prune [world class]

Rollout is not so clear.  The prosaic  24/21 15/14 is a statistical tie* with the hitting play, despite garnering no votes from the forum.  Why is it a good move?  It duplicates 2's.  2 to enter, and 2 to hit the remaining blots - obvious in retrospect, but I didn't see it over the board.  It also gets the runners moving, bringing them into contact with rkb's backmen. 

    1. Rollout          24/21 15/14                  MWC:  51.77%
       0.545 0.179 0.005 - 0.455 0.108 0.003 CL  51.27% CF  51.77%
      [0.001 0.001 0.000 - 0.001 0.000 0.000 CL   0.02% CF   0.03%]
        Truncated cubeful rollout (depth 11) with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861634383 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]
    2. Rollout          8/4*                         MWC:  51.73% ( -0.04%)
       0.531 0.220 0.007 - 0.469 0.123 0.004 CL  51.39% CF  51.73%
      [0.001 0.001 0.000 - 0.001 0.001 0.000 CL   0.02% CF   0.04%]
        Truncated cubeful rollout (depth 11) with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861634383 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]
    3. Rollout          24/20                        MWC:  51.60% ( -0.17%)
       0.541 0.175 0.005 - 0.459 0.109 0.002 CL  51.18% CF  51.60%
      [0.001 0.001 0.000 - 0.001 0.000 0.000 CL   0.02% CF   0.03%]
        Truncated cubeful rollout (depth 11) with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861634383 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]
    4. Rollout          15/11                        MWC:  51.55% ( -0.22%)
       0.535 0.185 0.005 - 0.465 0.111 0.003 CL  51.16% CF  51.55%
      [0.001 0.001 0.000 - 0.001 0.000 0.000 CL   0.02% CF   0.03%]
        Truncated cubeful rollout (depth 11) with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861634383 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]


* I don't consider my rollout settings to be authoritative, so any result this close is suspect.  The point is that it's close, and the choice is what kind of game do we want to play.

The prosaic move is still on top, but not by enough to say it's the "best" with any confidence. Maybe 2 ply     gives a different result?

    1. Rollout          24/21 15/14                  Eq.:  +0.296
       0.558 0.179 0.004 - 0.442 0.097 0.004 CL  +0.212 CF  +0.296
      [0.002 0.002 0.001 - 0.002 0.002 0.001 CL   0.005 CF   0.013]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861430848 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]
    2. Rollout          8/4*                         Eq.:  +0.286 ( -0.010)
       0.545 0.212 0.005 - 0.455 0.112 0.007 CL  +0.221 CF  +0.286
      [0.002 0.002 0.001 - 0.002 0.002 0.001 CL   0.006 CF   0.017]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861430848 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]
    3. Rollout          24/20                        Eq.:  +0.260 ( -0.036)
       0.554 0.171 0.004 - 0.446 0.101 0.004 CL  +0.191 CF  +0.260
      [0.002 0.002 0.000 - 0.002 0.002 0.001 CL   0.006 CF   0.014]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861430848 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]
    4. Rollout          15/11                        Eq.:  +0.239 ( -0.057)
       0.547 0.180 0.005 - 0.453 0.105 0.005 CL  +0.186 CF  +0.239
      [0.002 0.002 0.001 - 0.002 0.002 0.001 CL   0.006 CF   0.014]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 861430848 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]

8/4* is clearly best, although plays 2 and 3 win more games overall. The extra ~4% gammons the loose hit creates make it worth it, even more so at this matchscore.

    1. Rollout          8/4*                         Eq.:  +0,4309
        54,70  21,29   0,62 -  45,30  11,75   1,09 CL  +0,2318 CF  +0,4309
      [  0,09   0,08   0,03 -   0,09   0,10   0,08 CL   0,0028 CF   0,0056]
    2. Rollout          24/21 15/14                  Eq.:  +0,3690 ( -0,0619)
        55,70  17,12   0,33 -  44,30  10,81   0,96 CL  +0,2422 CF  +0,3690
      [  0,09   0,08   0,02 -   0,09   0,10   0,07 CL   0,0027 CF   0,0057]
    3. Rollout          24/20                        Eq.:  +0,3513 ( -0,0796)
        55,56  16,52   0,29 -  44,44  10,82   0,86 CL  +0,2298 CF  +0,3513
      [  0,09   0,08   0,02 -   0,09   0,10   0,06 CL   0,0027 CF   0,0056]
    4. Rollout          15/11                        Eq.:  +0,3307 ( -0,1002)
        54,48  17,62   0,33 -  45,52  11,34   1,07 CL  +0,2169 CF  +0,3307
      [  0,09   0,08   0,03 -   0,09   0,10   0,07 CL   0,0027 CF   0,0058]
        Full cubeful rollout with var.redn.
        6480 games, Mersenne Twister dice gen. with seed 860861592 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 2-ply cubeful prune [world class]