Things that I like about Best Wishes? Yeah. many.
1. For the first time, rivals for sidekicks* and many rivals for Ash. Some get more developed from other but it's fun to use.
2. We have 15 Gym Battles in one saga. And in 11 of them, Ash has participated. Other characters got 4 Gym Battles, things that never happen in the anime before. This is a step forward from 2 in Sinnoh and 0 in Hoenn.***
3. Something from the Unova league. The fact that the rivals are using pokemon that we know. One of the things that I don't like about the Sinnoh League is that the new rivals has new pokemon without using his known pokemon. (And Ash doesn't need to use the reserves in Sinnoh although I know why happened).
4. Unpredictability of battles. In many cases we don't know who will be the winner of the battles. (And if not for Terebi-Kun, I thought that Ash lose (or at least don't get the badge) against Homika and knowing one month ahead that Ash will win with Krookodile).
5. The attempt at the writers to think that the main cast will change but finally didn't end happening. This has happened three times in this series, Meowth Arc, Dawn's cameo and TR leaving.
6. I like Cilan and his "stating time" antics. And Iris is a well-developed character for be a "sidekick". And the BW chemistry trio has a good chemistry. At least is better than DP at least (DP had a one excellent chemistry (for me, the est chemistry of the show) but at expense of one weak and one damaged chemistry).
7. The Don battles. And in this saga, there 3 Don Battles. Although the Junior Cup was sightly dissapointing, the Don Battle has been a good method to show the rivals, have chemistry with other characters and where almost anyone but fight anyone. (Iris VS Stephan, Iris vs Burgundy, Ash vs Georgia and Bianca vs Georgia are good examples of this).
8. The animation. Although the stock animation could be annoyued at times, the animation is a notabloe difference from the DP series. And I think that any episode has "bad" animation like some of AG and DP.
9. The lack of fillers. In Best Wishes we had like 10 fillers. I like when almost every episode is important to the plot.
Things that I never mind of Best Wishes:
10. Pikachu being reset at the start of the saga. Seriously, doyou want for Ash to have the strength to the end of Sinnoh? And remember, Pikachu is the strongest pokemon of Ash although Pikachu was "resetted" at the start of BW. The same goes to Ash' reset.
11. The position that Ash will get at the end of the league specially if compared to other sagas.
12. That Ash scanned pokemon in the pokedex. Ash is the only main character with pokedex recurrently and the kids wants to know who is this pokemon. Although I don't like when Ash scan pokemon that he scanned "recently".
Things that we're obvious before that doesn't say in the show ut at the start of Best Wishes were said again and I love when that was said. 14. Particularly that Ash was 10 at the start of Unova saga. Because this resolves something that a first glance should be obvious. That the anime character doesn't age through the years. And passing through hand-drawn to HD =/= aging. Although Ash doesn't look exactly like a 10 years old since episode 1.
Things that I didn't like about the show.
I don't find talking too much on them, but I say two of relevance recently:
15. Trip. And not because he was a rookie at the start at Unova (Ash was technically a rookie at the start). And not because of the design. But because the big fluctuactions of development and the thought that I think that the writers don't like Trip, almost proven by his defeat in the 1st round of the Unova League (further supported from the early defeats at the Clubsplosion and Club Battle)**.
16. Iris vs Drayden. Well, Iris catches an overpowered Dragonite. That Dragonite sweeps the Junior Cup but doesn't obey Iris. When Dragonite went out of the control, Krookodile defeats him. Iris used him to fight the Therian Formes and Dragonite stays disobedient until the Village of the Dragons. Well, I can accept that. But I can't accpet that an already overpowered obedient Dragonite is defeated so easily with a Druddigon that's way overpowered than Dragonite. I hate that because Drayden is a strong Gym Leader, not Unova's Champion. I know now why Ash fought Roxie and not Drayden before (apart from the obvious).
And to end that, something that I don't accept negatives because of it:
The 2-partner being postponed and Team Plasma not appearing afterwards. If the 2-partner airs, I'll give an opinion. But seeing the people that died in the Tohoku earthquake (10.000+ people diuded there and we saw the second worst nuclear disaster of the history) not airing two episode of a cartoon would be a such big problem. Please, if you rant negatively about BW, don't use Team Plasma.
This is all.
*Sidekick. Sidekick is a main character that doesn't get much focus as the "star" of the shows. In Pokemon, the only official stars are Ash (all) and Dawn (DP). Although May was a borderline between star and sidekicks.
**There's a difference between Burgundy and Trip. First, that Burgundy is meant to be a joke character, Trip and specially his Conkeldurr aren't. And we know that Burgundy stays all the tournamnet that she takes part until the end. Trip leaves when his battle is over (and I see Trip leaving in just two days, trust me).
*** I'll put on tmy profile the 15 Gym Battle that Ash has had this saga.