Honestly, I think that what we saw in the Diamond and pearl series is as serious and mature as it needs to get, with maybe some more topics on death, romance, and career issues attached.
As for stuff like Pokemon using moves that don't make sense according to competitive battling, lets be honest here, they do that to make it look better for the big screen. And it's obvious that anime canon is very different according to game canon in numerous ways. Pokemon don't have all their levels set to 50, therefore, a bad-ass Pikachu could beat a maybe slightly less experienced and/or less motivated Latios. And we could have a f@&*ng Snivy prodigy kick your but (for better or for worse
) or Ash's Krabby get in there and kick but. The counter shield, the spin dodge, etc. I do think they should feature more pokemon battle strategies and scenarios reminiscent or partly reminiscent to possible video game situations, but if they totally revamped the anime logic to make it work like the video games then it would be kind of weird and a disservice to the world that they've already spent years building up.
If you want the public to know what competitive battling is just to "save the integrity of the Pokemon fandom" then what needs to happen is that viewing of the video game world championships needs to expand, and that's that. Which could take a while since last I checked I don't think any video game tournament has been deemed TV worthy as far as I know.
If people are going to make fun of us just because they think Pikachu is our favorite Pokemon or the Pokemon say their names or something stupid like that, then that's their problem. They are f@&*ng blind if they don't see TheJolteonMaster or SuperSkarmory or Marriland making videos on youtube (no Pikachus there) or all of the pictures and videos and fan art of Charizard and Blastoice and etc. And Darkrai on the cover of the movie or Zoroark or Lugia or Zekrom. Pikachu is an awesome mascott because, Pikachu wants to be who he wants (stay a Pikachu) no matter what anybody says yet he can still kick but, and gain respect. Pikachu might be the first thing they see, but if it is the only thing they see, then it's only because they don't care enough to pay attention.
My wants for the current anime: keep Charizard, even if he appears only once in a while. Cuteness is cool and all, but give us some variety please. Do more of what you did in D/P with the battle strategies and etc. Keep Ash's accomplishments in play.
My thoughts on an alternate anime: Meh, could be cool, but is it really necessary? Only thing that could set it apart from the current Anime is explicit sexual themes gore and violence and moral dilemmas, unless they kid-ify Ash's story even more which I would not like.
The best compromise I could come up with is slowly advance Ash's story into being the mature one and start a new Anime for the kids. But honestly, are explicit sexual themes and gore necessary in a Pokemon Anime? Do we want to separate the kids from the adults? Kids can take a lot more than you think you know. Part of the charm in Pokemon is that it's for everyone. :/
The best excuse for a more serious alternate anime is create a different Pokemon world and really dive into some deep and intense morale dilemmas and etc... actually that could be cool if they can do a kickass job in the world design department, make it like a dark version of what the Pokemon world could be. Maybe even connect it with the current Anime world somehow. If they got the budget there's an idea for a potentially kickass spin-off.