I don't disagree with any points you make in general, it's just that your 4th/5th OF shouldn't really be getting enough PAs to really carry any offensive difference making anyways over the course of the season. the offensive contribution of 250 PA at 80 wRC+ vs 120 wRC+ shouldn't make or break your season. Is it a margin that would be nice to take advantage of? Sure, but that's after you take care of the bigger needs. It's far more important that your regulars are hitting as well as they should be, not the Myles Straws of the world.
If deployed properly, you keep Straw away from the batters box as much as you can and keep him more in the pinch running/defensive replacement category rather than using him as a strict platoon. Have a bigger threat to take that pinch hitting role, then just deploy Straw to take over defensively.
I just sorted all the RHB that play CF and hit LHP well and there's literally no realistic targets that can play CF well defensively. So, saying we need a guy who can take over FT CF if Bateman sucks ... thats not the 5th OF nayway