In the case of Pidove, maybe the writers could give her some important wins outside of gym battles, maybe against Trip and/or Bianca sometime between now and the league. Because hey, wins against rivals are important too.
My prediction for teams, it has been awhile since I did one:
Ash:
Pikachu: .... do I really need to say anything? No move change, T-Bolt, Electro Ball, Volt Tackle, Iron tail, and Quick attack. Switched around every episode
Samurott: I really see Oshawott going all the way seeing as it seems to be Ash's main starter for the region. Becomes Dewott sometime before the 5th gym and finally becomes Samurott just before Drayden/Iris battle. Has powerful attacks like Megahorn, Aqua jet, Shell Blade, maybe Hydro Pump or even Night Slash (gives him another use for his blades)
Pignite: I see Tepig evolving not too long after Oshawott. I really see the guy starring against Hachiku. Moves: Nitro Charge, head smash replacing tackle, arm thrust or heck even superpower, maybe even Assurance because as someone said before Ash's pokemon tend to take a lot of damage in battle, plus flamethrower. Like Pikachu moves used switched around per battle. Might evolve into Emboar in filler saga
Snivy/Servine/Serperior: Ahh I love this little lady and I am terribly conflicted about where I want her to go. I'll accept any outcome really, even remaining unevolved as long as she kicks ***. Moves: Keep Leaf Storm, Leaf Blade, replace Vine whip with giga drain and/or twister. Keep Attract no reason to get rid of it. Add another annoying move maybe Glare plus an attack of another type aerial ace maybe.
Unfezant: no reason for this little birdie to not go all the way. Since she apparently wont fight Burgh, hopefully she'll star against Skyla. Plus sometime in between and/or after, she'll beat a few of Bianca and/or Trip's pokemon in battle. Moves: Detect, Steel Wing, Air Slash, Sky Attack, Hypnosis, Razor Wind.
Scrafty: I see this little guy staying a Scraggy for awhile, he might evolve around the same time Axew becomes a Haxorus, signifying their rivalry. He'll have High Jump Kick, Zen Headbutt, Faint Attack, not actually sure what else to give him. Will beat Haxorus win the 8th gym after a jaw dropper of a fight.
Leavanny: Will be Swadloon by BW 025 pretty much confirmed, will likely be a leavanny by the time Ash fighte Elesa.
Possible other reserves
Krokorok: Yes I know, but I still think Ash can catch the guy. But he'll stay the same for the duration of the saga, MAYBE evolving into Krookodile in a possible filler saga.
moves: Thunderfang, Dig, Stone Edge, Foul play, level ground, Outrage (too powerful for it too control at first, needs a bit of training with the move), Sand storm
Bouffolant: no Tauros comparison, just a power house of pokemon. Will be female and nicknamed Aloe. moves: Megahorn, Afro Break, Reversal(always wanted to see this one in the anime), Earthquake ( I know, Iknow but its been years since then) finally maybe Scary Face, XD Just kidding... mostly
Reniclus: powerful psychic with no definition of personal space, kinda like Muk. Potential to be Ash's first tank/wall. Forgot to add attacks: I would guess Psychic, Focus Blast, Psycho shock, Shadow Ball, Light screen, (something I wish Pikachu would learn) recover, hidden power. combination changes every battle.
That's really it as far as I can think of.