[Taqwus]

Right now, their utter randomness in picking targets and the fact that a province has to choose between hiring an assassin (whose odds of accomplishing anything are fairly low -- even independent priests fairly frequently survive, due to guards) or hiring a commander that will probably have far greater returns over time.

I could see an assassin having some control over *whom* to target among commanders in a province. This does not mean that they should deterministically be given an opportunity to try against that commander; i.e. it is entirely reasonable that one have to wait around for quite some months avoiding patrols before finding a opportune time (depending on the patrol value in the province, for instance... and the target being in a castle should probably add a penalty as well).

Second, it doesn't mean that they should have a good chance of survival if they've pulled off the assassination -- it should, minimally, have a large penalty to the assassin's stealth for a while (possibly permanent). Think, say, Jing Ke; he had a plan that gave a shot at getting close to the Qin leader, but no plan that would have caused the courtiers from disseminating his identity and having patrols looking specifically for him even if he'd been able to get away. The odds that an assassin has 'blown cover' by trying should be rather high, even if the target and personal guards are all killed.