Mate... Pokèmon used to be battles and winning fights and catching them all.... Not fackin' dress up... I didn't pay for that pansy stuff... Plus... My fire guy wasn't strong enough to beat 3/4 final bosses...
..... /turns hat backwards - Time for another one of my rants....
Pokemon aren't just mindless soldiers you throw into combat. Many people in the Pokemon universe have Pokemon as pets. What do people do with their pets? Have them compete in various competitions to prove they are the best. This includes: Fashion shows, battling, Poke-lympics of sorts, and style competitions. The idea of the games is to raise the creatures as you would your own fantasy pets. Some people want cute ones, others want strong ones, and some even want the ones nobody wants. To me, Pokemon is a way for me to live out a dream I can never accomplish: Travel all over, make new friends, challenge myself in ways that almost seem impossible.
Pokemon is still very much so "Gotta catch'em all". However, new things have been added for those who want to do something else with their Pokemon. Battles have changed, the Pokemon have changed, the mechanics have changed, the fun has not. If one change caused you to throw away the game, then why bother playing any sequel ever? Every game that has a follow-up has changed something from the original, sometimes for the better, sometimes for the worse. It's a game. The idea is for you to experience the changes. Most games, if you don't like the changes, there are ways around them, i.e. don't do the fucking fashion show in the first place.
Also, if you were seriously relying on a single Pokemon for the entire game, you need a wake-up call. Pokemon is a strategy game, not a "Mash the A button every fight to win" game. One Pokemon will not get you anywhere. You need a team, a team that covers most of your weaknesses. Here's an example: I take it you were using Emboar, the final evolution of the fire starter. Its types are Fire and Fighting, meaning it can easily deal with Ice, Normal, Grass, Dark, Steel, Bug, and to some extent, Rock types. Not bad, but it's also weak to Flying, Psychic, Water, and Ground, while half of your same-type attacks will be not very effective against Poison and Dragon, and The Fighting half of your moves are completely useless against Ghost. You see? The odds are against you if you only use one Pokemon. This is why you're allowed to carry 6. Build a team, cover your defenses, and battle smartly, or your opponent won't even lose a single Pokemon before you're knocked out. Plan out your moves, predict your opponent, and go. Don't believe that works? Here's a story of mine: I was playing Platinum version, and I finally got to the champion. I thought that I would be allowed a break in the next room, so I didn't heal my Pokemon. The battle auto-commences when you enter the room, and I had only two Pokemon at half health, and the rest were k.o'd. I carefully made a plan, managed to revive whatever Pokemon I needed, and took down the champ without losing one Pokemon. It's all in the strategy.