I love the new character creation system. Moving ASIs to background and getting stuff like languages and tool proficiencies from the background in addition to skills makes your background feel like just as important a part of your character as your race choice is. It being customizable by default is even better as you can expect most people to have had very different life experiences and training growing up. The starting feat is just icing on the cake. Especially with leveled feats so that there aren't any obvious auto-pick feats at level 1 like Greatweapon Master overshadowing feats like Skilled or Crafter.
Though some of the suggested language/background combos were kind of weird. Like a sailor knowing Primordial because they... Spend a lot of time at sea? And the sea have elementals in it?
Love orc being a full core race now. I know orcs already had Powerful Build but giving that trait to a now core race does a much better job of representing the "biological strength disparity" issue than a flat +2 did. With Powerful Build an orc wizard that dumped strength to 8 can lift about 480 pounds, which is equal to an elf with 16 strength. That's huge. It means an orc genuinely is just naturally massively physically strong even if they've spent their years reading books instead of training.
I do feel half-breeds got a little shafted in how this was implemented though. Half-orcs are now mechanically the same as pure orcs or pure humans. At the same time though I am unsure how else to treat this without making it possible to min-max race combos to get overpowered results. I imagine most players don't want to play with an aarakocra/yuan-ti hybrid that exists just for the racial ability mixing.
Ardlings seem interesting. Having a celestial equivalent to tieflings in the core book makes sense, though I am surprised they didn't just use aasimar given the Ardlings seem to use very similar abilities to what aasimar enjoy. I do think Ardlings are more flavorful and distinct as a race than aasimar though. The animal head is as obvious a tell as the tieflings' horns and eyes.
Dragonborn finally have darkvision! Finally. Them being the only dragon-related species in the multiverse without it was really weird. That said they're still a little weak on the racial side in my opinion. I wish they'd taken more from FIzban's. If not Powerful Build wouldn't go amiss on the Dragonborn given they are supposed to be naturally stronger and tougher than other races anyway. Or they can finally get a bite or claw natural weapon or something. I dunno why but Wizards always seems to be very reserved with their dragon race compared to all the stuff they give elves and tieflings.