Now I don't know who Casey will start, but I'd prefer Amir's strong D and versatility there on the starting unit, and Tyler's energy and how that can help the team off the bench. I think in the end, they will both be getting 25-30 minutes so it's on Casey to utilize the rotation properly to maximize both. So both should be able to thrive on the same team without taking anything away from each other.
I also think Tyler would get more opportunities on the 2nd unit, as he does have a better offensive game (with the ball in his hands) than Amir, and there just won't be any touches left with JV, Rudy, DeMar and Kyle on the starting unit. I would also always want one of him or JV on the floor if possible, so I'd stagger their minutes (harder to do if they start together) as they are the best post threats and will thus help open things up for the wings.