It depends on personal opinion and taste. If they look cool to you, there's nothing more to it. However, if you want do go technical - the desings has changed alot, with each gen bringing new and innovative ideas forth.
It's only because of the sentiment old fans have for the originals, so it's completley fine to say they're bad for you, however that doesn't make it true for some one else.
Well, there's been some good points brought up here that I wouldn't have thought of otherwise. It's enriched my life! ^_^
Nope. All Pokemon deserve equal praise.
No. The first Pokemon you were introduced to, often, are the ones you hold most dear. So therefore, it's only logical that you think that they look the best. I know that I will never like a generation better than I like Hoenn, as those were my first games. I'm not saying I don't like other Pokemon, in fact, many of my favourites come from Gens 4 and 5. But overall, I really like Gen 3. And I'm glad you're not one of the people who started with Kanto and only likes Kanto. But sadly, a lot of people only like Kanto. It had a LOT to do with the gen you started on.