Ok. look, no offense, Art Critic Cubone, but i kind of disagree with you on some points.
First off, D/P Pokemon are the staple. May I point out that Aipom has a fourth generation evolution, and Bonsly evolving into Sudowoodo does not necessarily mean that fourth-gen Pokemon aren't being sold? I think the point of Bonsly evolving was to remind all of us that Bonsly is in fact the pre-evo of something.
no offense, but even if we dismiss Aipom and Bonsly as promoting the 4th gen (even though Bonsly is debatable, considering that even young kids would know that Bonsly evolved into Sudowoodo thanks to the Pokemon Strategy guides having pictures.), we still have Team Rocket's pokemon. I mean, while you could argue that Meowth is only in it because he is the face of Team Rocket (similar to how people thought Pikachu was the face of Ash's Group. (And in essence, the franchise)), the other pre-gen pokemon (Cacnea, Dustox, Seviper, and Wobbuffet) aren't even supposed to be there at all if the writers were only going to focus on Gen-IV Pokemon. I mean, none of them are new pokemon introduced in Gen IV, nor do they have evolutions for Gen IV, nor do they even have Gen IV Pre-evolutions. In fact, out of all the AG Gen III Pokemon that JJM Caught in Someway or another, the only one that even fits with Gen IV is James' Chimecho (since it has a Pre-evo in that region), and that Pokemon is currently recovering from an illness while Mime Jr. Takes over!
In addition, it would actually be out of character for Paul to release Chimchar. Have you noticed that every single time he has released a Pokemon, with the exception of Azumarill, he has done it after or almost immediately after capturing them? Actually, come to think of it, there's no way to prove that Azumarill wasn't a recent capture as well, unless someone out there knows more then I do. This leads me to believe that Paul doesn't just randomly throw Pokemon he's been carrying around forever away- he makes an initial guesstimate of their power and lets 'em go or keeps the little buggers, depending on his mood. You'll notice that Elekid, Chimchar, and Torterra at least, have been with him for a while and seem to identify with him.
While I do somewhat agree with you in regards to that (the whole thing about only releasing captures that were recent), that doesn't necessarily mean that he can't release it, period. Need I Remind you that He released the Starly with Aerial Ace despite the fact that he won against Ash's Starly? And anyways, considering that His Chimchar was defeated more times than it won on screen (currently 3 losses and 1 win) and was hinted at the very same episode of it's debut that it lost quite a bit before he met Ash (he said "Still as weak as Usual, eh?" After it lost to Aipom.) He might eventually find it to be a lost cause and then release it. Though he might not go as far of releasing it as Damian did (like leaving it out there to die in the rain), it might still be very harsh. Though I wouldn't go so far as to say that it is OOC of Paul, what would be OOC for him is suddenly having him act like Ash with his Pokemon.
Moving on from that, there's no reason Ash needs a fire type. He didn't have one in Battle Frontier, he doesn't need one now. In fact, I'm strongly leaning towards the idea that the writers are slowly moving away from the type-showcasing trend, and trying to show off other types.
So? He didn't really have a grass-type or a flying type in Battle Frontier, either, and that didn't really stop him from catching Starly/Staravia and Turtwig (And before you mention Swellow and Grovyle/Sceptile, those don't count since he brought them over from HOENN, he never caught them within the Kanto region, which is what I assume what you meant by never having one in BF, now if you meant one on his team, I wouldn't really say that considering that he used Torkoal in his first match against Brandon. (the Registeel match)) No offense to you or anyone else, Art Critic Cubone, Just Stating some points.
Anyways, as I have stated before, he just might get a fire type this region since he already caught a flying type and a grass type (if they truly didn't him to get the fire type, they also wouldn't have given him the grass type and the flying type.), just because it is the 4th gen doesn't really mean that they can't have pre-gen pokemon (as evidenced by the likes of Ash's Ambipom, Brock's Sudowoodo, and the majority of Team Rockets pokemon (really, besides Meowth since he is the face of team rocket, none of their pokemon should be in this region considering that none of them have any relation to Generation 4, IF the writers were indeed intending to market only 4th Gen Pokemon, which I sincerely doubt considering Sudowoodo, Aipom, and the majority of Team Rocket's Pokemon.), heck, he might even catch a pre-gen fire type.