Honestly, I loved the assassinations from Halo 5: Guardians. For example, take Back Breaker and Nice Try. Those ones, to me, are pretty good! (And some were pretty humorous) And, if they’re using Reach’s customization, then they should go all the way. You should be able to customize your assassination, like take parts from some assassinations, and put ‘em together for a Frankenstein of an assassination!
I think that instead of using micro transactions, you unlock the customizations as you go, like what they did with Reach.
But, that’s just a hope, and I don’t think even a year is long enough for 343 to come up with a customization system like this. Not just assassinations, but the entire system itself.
[NOTE: 343, WHATEVER YOU DO WITH INFINITE, DO NOT PUT RUSSET IN IT.]