Favorites has been a rollercoaster really.
Like when the starters were revealed, i didn't have a preferred starter, i'd probably rate Rowlet slightly lower than the other 2 but it's not like a direct hate. once the 2nd stages were released i instantly liked Brionne, and placed Torracat last. when Datamines happened, Primarina lost a bit of points from me due to all the extra bells and whistles it gained whilst the other 2 were remotely balanced with Dartrix in a slight lead. (but not as much as Brionne sticking out from the other 2)
I guess now that there's footage, Primarina's dislike has gone down for me, Incineroar is a clear winner. i'm not even sure what i was expecting with Decidueye, i think it's mostly the long owl legs that's a turnoff for me, the idea of an archer is cool but i was't expecting for it's claws to be hidden, was expecting something more of a Hawlucha where you could actually see hand-claws. i almost got put off by Incineroar's Anime art leak just because of the cartoony limbs which gave off Werehog vibes, however the Heel wrestler and cartoonish James Turner eyes/hands really makes it pretty expressive.
All in all, all 3 starters are probably balanced for me. they all got divergent designs and creative typing which puts them apart from other single-type hidden ability users. i think after Oshawott, people probably havn't hated Popplio as much, not like they're Pignite or Quilladin, and even then, even Chespin was slightly derivative of Oshawott who in turn derived from Piplup. i don't think it would have ended as worse as Delphox, Chesnaught seems like it'd be undoubtedly average if not for Greninja's battle utility and promotion avert it's unusual appearance. (the tongue scarf, mostly)