Suikoden 2 is one of my all time favorite rpgs EVER. In my old age I've soured a lot toward jrpgs I use to play obsessively as a kid, but certain outliers, like Final Fantasy 3 and Chrono Trigger are still loads of awesomeness. Suikoden 2 is one of those games, Luca Blight was such a great bad guy, one of my favorites EVER, the first game kinda felt lacking with the bad guys since most of them were usually under the control of the witch lady and The Emperor was a pretty nice guy, all things considered. I really felt bad for him at the end.
Suikoden 2 is the best, objectively, to me, in my opinion, which kinda contradicts being objective but whatever. Still, a person needs to play through the original just so they can get to recruit S1 protagonist later for MUCH AWESOMENESS. I do prefer Tir to S2 guy, I was disapointed I didn't get to pick the dark sword rune and instead got the "wee friendship is power" brightshield rune. Soul eater was SO awesome, it had badass spell names like HELL's FINGERS and JUDGEMENT and can you forget that sound of doom it made while devouring enemies' souls?
So yeah..
S1 protagonist > S2 protagonist
For everything else..Suikoden 2 is better.