[Trexmaster]

I'll be honest on my role character I don't even use a build on them because to me it just wouldn't feel right.

It's an open secret they're an extremely proficient healer, yet because I'm not an Elf I cannot in fact heal better than one, mechanically speaking, and this fact would get leveraged against me if I tried to represent my character mechanically. This is a quick and minor example of how these things make it difficult, as per the OP, to mechanically represent characters with narrative strengths like that.

In a world where they actually could mechanically heal better it'd change nothing but allow to me participate in relevant events' mechanical portions without needing to attach an EM to myself at all times to prevent having people go 'wow you're not actually that great huh'. Which while ICly my character doesn't care and would rather people think that I'd like to be able to leverage that ability when it matters, instead of being confined to never participate in mechanical PvE events ever with that character.

GMs/EMs are basically already given these permissions at least when it comes to events. Though I believe it should be treated the same way as applications where it should go through the same process as players to give such characters approval to be 'stronger' in a mechanical capacity for fairness sake, and so such things can be reviewed by their peers to ensure no foul play comes of it.