I agree. The biggest problem with the way Feats worked in 3E, and to some extent 4E was that rather than enabling stuff, many of them effectively made "cool stuff" impossible or heavily penalized by default, and then you had to buy the Feat to re-enable it.
That's not a good approach for D&D generally, I'd say.
It's a really really bad approach when Feats are competing against ASIs and not something you get many of.
Feats in 5E should be used for stuff that people are going to do over and over, and want an additional bonus doing. Not stuff that's likely to occur very rarely and be exceptional and exciting like this seems likely to be. I'd rather see some sort of house-rule that made it extremely risky, and quite rewarding (but the important thing is to ensure there's a large enough chance to screw it up that you won't just use it on every possible encounter - if you would use it on literally every encounter, then it is good Feat material).