abirdcall
(she/her)
Thankfully, this isn't 3rd edition. If a player can fluff it in a way that fits with their character, there's no reason not to go along with it.
Yeah, it is 5e which means it is even worse to abuse rules like this. The rules are written for clarity and ease of play are not written to avoid abuse. It is assumed that players aren't going to abuse them.
I don't really get it, if you really want to abuse rules why not just make your characters higher level. It accomplishes the greater power level that you are looking for without the deception.
As for Hex, it is a workhorse. You don't need to take it for your Warlock to be good, it is just that it is the standard.