Komodo Dragons Rule!
Now this is a more solid taboo opinion. Though it is a criticism I've seen elsewhere but one I can agree with, not all character focus was great in SMI reckon this is unpopular, but I think SM had the right idea of having a big cast, just it wasn't executed great. Ash works better with a lot of different characters to bounce off of and generally the show feels more vibrant with a bigger variety of chemistries and interactions. When only one or two characters take over, it usually gets a bit dull.
SM's bigger problem was individual development, and even that felt owed more to how much time it wasted. I feel they could have easily fit in plenty for all six characters, but it took until the eleventh hour to bother with big change ups for half of them. Reminder that Sandy, Shaymin and Meltan only appeared midway into the last season, while the only capture in the second was Poipole. Even worse the former two were only their trainer's second Pokemon. Meanwhile I think the only contender in a previous series is Dawn's Togekiss, and even then Dawn had PLENTY of captures and development beforehand.
Even with that however, SM was a lot of fun dynamic wise, and I think a lot of characters shine just as well as foils than through arcs.