as a "vet" (honestly I hate using the term) I think the melee changes are a wonderful breath of fresh air. I feel there is more depth and interaction with your melee weapons now. (granted some stances still feel shallow, especially ones that only had two different combo's prior to the update... I think some more work needs to go into some of the existing stances to be more interesting like other stances)
granted I'm not one of those players that does 5 hours of endless missions or fight lv 150+ enemies on the regular but I do, do sorties and Kuva lich missions which do have higher level enemies (70+) and to be frank the new melee changes has had me confidently use weapons that I'd never consider for even that level of content with minimal issues.
Yes it was a little bit of a "wth?" when I first played the update myself but on the whole I feel it is all an improvement. yes I'm a little annoyed I need to relearn all my memorized combo lists and some of my "go to" weapons but honestly, I think its good. using the same things over and over makes things stale.