Steven's steel type usage makes a good champion out of him...... but Red is awesome and so is Lance.
But, between Steven and Wallace I would prefer Steven. Personally, in my opinion Red's Charizard is way too
awesome and so is Lance's Dragonite.

I preferred Steven as the Hoenn Champion. He had a history with the player, just as all of the other champions do for their respective players. Granted, Wallace was involved at the last moment in the lead up to the Emerald climax, but even then, Steven still had more involvement. At least they gave him a role similar to Red's in Emerald, but I like his character better, overall.

It doesn't help that Game Freak basically replaced the Sootopolis Gym Leader position with a carbon copy of Wallace, so they were basically saying "Hey, I know you've beaten me once already, but I wanna rematch, so I talked the actual champion into letting me fight you instead".

At least the other champions had more variety and challenge in their teams, and that includes Lance, the guy with the three Dragonites… alright, so maybe not Lance, he did have six flying types, even if flying is a subtype… And maybe Iris, but I've only ever fought her once, and I don't quite remember her team at the moment. Other than her having dragons.

…

[/rant]

...

Milotic did scare/very much annoy me when I was younger, though, in both of his positions...

Yeah, I didn't realize either, but according to the manga, he does die, and then gets revived by Celebi.
Apparently, they had taken steps to prevent Kyogre and Groudon from being resurrected - one of which was to seal the undersea chamber, the other was to have the Regis scattered in such a way that they could be retrieved with the appropriate keys to the locks - the relicanth, wailord, and the various acts.

Knowing he might suffer trauma, Steven stepped down and promoted Wallace to the champion (he rightfully was the champ, just didn't want the position or something). Anyway, controlling the Regis was a bit much, and he died wielding the power.

(Just felt I should make a mention).

Me. I did beat both of them, after all.

I choose steven because he have å cradily

Going to go with Steven here. It's not a huge difference, but Steven's got a bit more variety in his team. He's got a few steel types in there which is really solid, compliments the rock and ground types pretty well, and seems more fitting for a champ. And like Kiga said, Wallace feels like a Sootopolis gym leader clone. Someone the player actually knows a bit instead of some random nub fits better too.

Steven bay far. Wallace was cool and all but Steven is in a whole other category, he is a frontier brain. Way better champ.

I don't have Emerald so I can't say anything about Wallace. But Steven was interesting to face the first time. Up to that point in the game there aren't a lot of Steel types (let alone the ones that are that strong) so it's a challenge to battle them all of a sudden.

I always liked Wallace, personally. It could be because I have the fondest memories of Emerald overall. Needless to say, Steven was fantastic too.