Alright, here's my very long winded (edit: and ye gods this ended up long XD), honest opinion on the Anime, and there's no real science behind it. If others don't agree, good for them. They can answer for themselves. Yeah, you said it's not a personal question, but for me it more or less is. There are reasons why I personally enjoy it and watch it. And if you read through this ramble, you shall see why. Kinda ^^;
The thing that really drew me into the Anime originally was because it was a mix of a few of my favourite things: Anime, and animals/monsters. Safe to say, the same formula is also what drew me into the games: RPGs and animals/monsters. I was pretty much hooked immediately: taped the first episode, rewatched it again straight after, and repeatedly listened to the intro over and over again until I'd memorized it. Back then, the show could do no wrong. I loved the corniness, the plots were decent, the battles were awesome, and it was just fun seeing all the different Pokemon in Anime form.
So, time went on. Didn't love the constant reruns, but I still loved the show. When the Orange Islands started and Brock left I was a bit bugged, but I soon got over it. I personally LOVED the Orange League - possibly more than the Indigo League on a whole. Still love it, too (recently started rewatching the Orange Island episodes and they're just as good as I remember).
Johto Journeys was my first real "meh" moment with the series. I think it's a mixture of reasons really. G/S couldn't hold my attention, so I didn't have that extra source fueling me to watch. The beginning of the show also felt very repetitive, most likely because it was back to the standard "main series" formula while the Orange Islands had really broken out of that mold. Then there was the slow transition into Ash's new team. Yeah, I didn't particularly want to see the Kanto Pokemon go, but it was inevitable. Very obviously inevitable. I'm truly surprised how long they kept Bulbasaur around for because it was more or less pointless (and that's funny coming from me because I love Bulbasaur to pieces). Ash just didn't need two Grass Pokemon.
Maybe this is why I loved the start of Hoenn so much. It immediately sent all of Ash's Johto Pokemon away, leaving him with only Pikachu to start and rebuild in the new region. I won't say Johto was all bad, though. It had its moments, and by the time Johto League Champions had rolled around I was heavily interested in the show again (thank "Wired for Battle" for that feat). "Fly me to the Moon", one of the first MQ episodes, is STILL one of my all-time favourite Pokemon episodes.
Anyways, I'm gonna emphasis how I "loved the start" of Hoenn. I truly did. We had two new characters join the cast, Ash DIDN'T get all the starters as usual, and Contests had been introduced which, very unlike the games, were actually pretty cool. I was also watching the show in Japanese for the first time, and there's no denying the impact that had on my early Hoenn enjoyment. It was just different, and for a show that repetitive different was a good thing.
As Hoenn went on though... Well, it was the opposite of Johto IMO. While Johto got better as it went, Hoenn seemed to get worse. Maybe it's because we were getting the same rehashed plots for the third time now, or the fact that Max had outstayed his pointless welcome. It certainly wasn't Ash's Pokemon - if anything, they were the highlight of the series. I really enjoyed the fact that they evolved the majority of his team. It always seemed odd how most of his championship opponents had fully evolved Pokemon and Ash heavily lacked in 'em. There was no reason for that.
One thing Hoenn kinda skimped on, though, was the amount of Pokemon Ash caught in total. He only had five Hoenn Pokemon. Yeah, I was all for him not using his previous region Pokemon for the Hoenn League, but it would've been much better if he'd had a few extras to swap in. Not that the league battles still didn't rock. Repetitive Pokemon choices aside, I found them overall better than the majority of Johto's league matches.
Now, can't really comment on how Battle Frontier has been dealt with by the dub. I've only seen the first few episodes of it that were dubbed by 4Kids, and the majority have all been quite good. When it comes to that season, the Japanese Anime is mostly what I go off of, and seriously... it rocked. Hard. Compared to the second half of the Hoenn saga, Battle Frontier was a breath of fresh air. It was like the Orange Islands all over again. As great as it is meeting a new Pokemon every episode, the episodes that don't revolve around that always seem better. Better quality plots n' such. I think that's one of the main reasons why I enjoyed both of the non-gym league seasons so much.
But here's the catch. So far, DP has -not- focused every episode around meeting a new Pokemon, instead opting for a feel that seems more like the Battle Frontier episodes. Maybe it's because there's a serious lack of new Pokemon this gen. If so, not complaining at all. It's too early to say if this new season will keep up the momentum, but it's definitely off to a great start.
So... uh. Yeah. Has the show gotten better? I'd say yes, because Battle Frontier was an awesome season and DP is shaping up to be just as good. That's very much on the short-term, though. Overall, the series has had its ups and downs, and it'll always have a distinct rehashed feel since it is aimed at kids and promoting the games, but I've always relatively enjoyed it. Enough to keep watching, at least. Maybe it's because the main reasons I watch it at all is to see the various Pokemon and experience some cool battles. The show is familiar to me, it's light/laid back and fun (thus a good thing to unwind to), and there are a lot of repetitive aspects of it I've come to accept and even enjoy. Namely, Team Rocket. You get rid of TR, you kill the show - simple as that. Anyone who doesn't love those three by now is taking the show way too seriously
And Pikachu. They're never gonna get rid of Pikachu. Deal with it. Accept it. EMBRACE THE PIKA!
Really, the show still retains a bit of that "can do no wrong" feeling for me because it is, after all, Pokemon. There are times it drives me insane - times I wonder WTF the writers were smoking - but still, for the reasons that I enjoy it, I'll probably always keep on enjoying it. Unless both the show and games become really boring, like what happened to me during Johto Journeys. But hey, I bounced back from that. Probably could easily do it again, too.
Now, compared with something like Pokemon Adventures, the Anime doesn't even come close. If they made an OAV out of that I'd be ecstatic ;D But again, I've come to accept why the Anime is the way it is, and I'm cool with that. While I'd like to see something at the quality of the manga, I wouldn't want to see it take the place of the current series (hence why I say OAV). I'm just not ready to let go of Ash n' the crew ^^;