I'd say it's the choice of making their endgame goals? I have this tendencies to either make them all suffer or give them an ending that would be open for anyone to interpret. I still wanted to give them all happy endings though.

for dr moby anything that requires commitment whether by choice or even forced is challenging for em eventhough ppl around em are willing to help they still insist on doin it themselves bc they dont wanna feel helpless (although they will later lol)

First thing that came to mind is whether he should get up and go to that meeting he has and risk nudging Skadi awake or if he should just be late and get an earful from Kal'tsit after

He always picks the 2nd option because he loves his wife but its still difficult

I dont have an "Arknights" OC per say, but I do have A multiverse OC, with Focus on Pokemon and Ace Attorney.

Anything to do with shopping. Tau would be so indecisive when it comes to finding a good deal that the time spent deciding on where/what to buy takes longer than it would for any of the products to be delivered to him