Yup. On the face of it A5e looks like the good parts of 3e customization+flavor but in 5e- which I like. For example their herald (paladin) has smites, but SMITE isnt the biggest mechanical identify of the class.So something like: extra work needed to rebalance the game?
Their maneuvers are kind of Book of Nine Swords for 5e- it makes martials very cool.
On the

And the origins, heritage/culture/background/destiny, are going to make the PCs surprisingly powerful out of the gate. You can easily have two resistances to common damage types, for instance, plus a host of other cool but very powerful options. Heck, you can even be sometimes immune to fire or lightning or whatever. It reminded me of the original 5e yuan-ti

They had a lot of designers working on separate sections of the books with not enough communication- which results in some weird stuff or interactions because they didn't seem to have a really solid editor. For example there are some maneuvers which sound really cool- like Defy Magic. But it turns out that there are only 2-3 creatures in the entire Monstrous Menagerie that this'll be worth using on at the level that the Herald can get this maneuver, because it only works on spell attacks, meaning attack rolls. And the herald only knows 6 maneuvers- this is a trap choice unless you house-rule it to expand its usefulness.
Some maneuvers are just plain OP, but you won't know it 'til the fighter is 5th level and using Stunning Assault in every encounter. So you have to house-rule it to be useful but not ridiculously good.
And then there are some classes, like the Berserker. Apparently the designer of the berserker thought the 5e barbarian was incredibly weak, because they took what is probably a 7 or 8/10 class and cranked it up to 12. Heavy armor, evasion, danger sense, expanded crits which will blind creatures with no save, and a couple subclasses that are so clearly better than every other option that after all this you should really just toss in the towel and use the 5e barbarian instead.
That being said, I still run A5e and their T&T book and MM are fantastic. Buuut I am open to checking out other options when it comes to classes etc.