Thus, which one of these mighty champions is your favorite?
Probably Garchomp.

What do you like, or dislike, about their designs, origins and such?
Dragonite: Like most Gen I Pokemon, Dragonite's design feels fairly uninspired, and it doesn't mesh with its pre-evolutions at all (whose designs I prefer quite a bit more). The uninspired-ness isn't as severe as some other Gen I Pokemon, but it's still up there. Honestly Dragonite's just pretty meh to me.
Tyranitar: I can't remember what motivated me to train one, but I did, and Gojira's done great things for me. I also personally enjoy its design, I think it's the cool spikes and armour holes. Its typing lets it down a little, but all in all it's a Pokemon I like.
Metagross: It's cool an unique, especially among the Pseudos. I do like it, but it's probably around the middle of the list.
Salamence: The design is kinda uninspired, but there's something about it that looks cool enough that I don't really mind. I've only ever used one in a rental team so I could earn enough BP to get good items, but it was pretty good when I used it.
Garchomp: Love it. It's a freakin' land shark dude! The design is pure gold (like most in Gen IV), it hits fast and hard, and it's just all around awesome.
Hydreigon: The design is just pure unadulterated badass. I just love it. Also, Soki's right, sockpuppet hands dude.
Goodra: Bottom of the list. Easily. I can see how some people could like it and find it kinda cute, but I'm generally grossed out by goop in general, so making a whole dragon out of it just really turns me off. Its typing is unfortunate too. I always feel like it should be part Water Type.
Kommo-o: I like it, it's a cool punching dragon with rattly scales. I've been using one recently and I like how it handles. Can't wait to finish USUM so I can throw Clangorous Soulblaze onto it and really see what it can do. I personally don't feel like it was the best direction to take for Jangmo-o, but that doesn't stop me from loving it.

What are your experiences raising one?
I've only ever raised them in post-game. You always find them way too late, and they take way too long to grow to make them useful in main-game.So the raising process itself has always been pretty smooth for me.

Does it tend to take you a long time?
Not me personally, since post-game, but I know it'd take forever to do if I tried in main-game.

Does it feel rewarding in the end?
Well, yeah, they're cool and strong.

Do you tend to stray away from such usage?
Indeed I do, see questions 3 & 4

Is there a certain kind of pseudo legendary that you yearn to see in future Pokemon games?
They don't bother me as much as they seem to bother some other people, but something different and outside the box like Metagross would be cool. As opposed to more Dragons/draconics.