1) Yeah the trinity is so commonly wanted by audiences that it should be standard where possible.
2) I honestly would mind if the anal scene is the same as vaginal in another hole. If the dev has the resources then it's a great way to make the character feel more fleshed out by taking time to show us how they would react differently to vaginal and anal. For example:
A "Good girl" like Opal might be saving her pussy for the right guy while she gives up her ass first because she just really wants to experiment and she needs to let out her horny.
Jinora might be a manipulative girl that offers vaginal purely because she wants the MC to chose her over Korra, then realizes that he wants anal too and she doesn't know if she's ready.
You get the idea. You could come up with ways to make all the girls more interesting by using the different scenes to express who they are. It would be a missed opportunity to just make them the same with holes being swapped.
3) By Rogue-Like are you referring to this game?
https://f95zone.to/threads/rogue-like-evolution-v0-994h-oni.14/