Considering the 'safe' play 13/5 13/9(2), and 13/9(3) 11/7 or 13/9 (2) 11/3 as well.
Hitting the runner 6/2*(2) isn't an option, I think, because I have to rebuild my board after that and you still have your 6-prime.
Point is: I want that prime too.
Making the 'safe' play might be too passive. You only need a 5 to escape, with 5-5 or 5-6 you're away, and 5-4 you'll hit. Otherwise, 5-1 or 5-2 will turn your 6-prime into a 5 and it gives me the chance to hit. you also have 1-4 to escape. But if you don't roll all that? There is a chance you'll have to break your prime and there's a small chance you make your 3-point and hold the prime (6-5) - but in that case you have to roll another 5 to escape, so that will be a big dilemma.
13/9(3) 11/7: 5 and 4-1 will hit. 5-3, 5-4, 5-5, 5-6 are bad for me; 5-1 and 5-2 breaks your prime, but the next roll you probably will be away.
But if you don't roll that 4-1 or 5... I think you still have your chances. I only have a 2 or double 1 then to make my 6-prime.
13/9(2) 11/3: 1 or 6-5 will hit. With all other 5's you'll escape, but with a better chance for me to hit the runner next roll, and 5-1 and 5-2 will again put you in the position of breaking your prime.
1-4 is a dangerous roll for me, because you will hit and escape and I'm on the bar with the risk of staying there for a while. You might also hit my second blot after that and then the best scenario for me is a backgame. Otherwise: 1-2, 1-3, 1-5, 1-6 spoils your prime.
Still I think it's the best play: with 6-2 or 2-2 I have my prime. With double 1 I can make the bar-point... and I like that play most, which is more intuition then good thinking.
So 13/9(2) 11/3 it will be.