i've always wanted to see a topic of this kind in every suikoden, knowing that ninjaluc started one for suikoden 2, it's way better and more useful than favorite topics. I'll cheer you up with this work, but guess you will face alot of negative comments, hope you don't mind to bear with mine first
-Flik: i won't rate him this high, he has good physical stats and decent but not high magical potential(got just one 4th spell at lv60), participate in a decent unite of x2 damage but requires 3 persons who are all short range fighters, this will bug us in forming party. Bref, He does his best at: freewill/healer/unite. He doesnt stand out in both regular and boss battle. Flik fan must have prepared rotten tomatoes waitting for me, but i will put him to 2nd tier at best.
-Cleo: a little correction, she can equip heavy helmet but not armor, but it doesnt affect her rank since shes not going to tank anyway.
-Kirkis/sylvina/stallion: each of them alone won't be much of a deal since their str/magic growth aren't great. But when they are together , that makes a good cover all tactic, Stallion got us "holy" rune, Kirkis/Sylvina have decent magic to hold support/offensive runes, in regular battle 2 of them could perform the hitall unite while in boss battle they can co-op for x2 damage. So i'd like to add this whole team to your 2nd tier list.
-Sheena:Magical Flik with fixed regular rune and no shield? i'd move him out of your list, even teaming up with his mama and papa won't bring much benefit.
-Ronnie Bell should stay there, she has weaker defence set but higher damage potential thanks to claw growth stats(compared to Valeria)
-Camille: i don't see much usage for her, her only good stats is skill which meant to help with normal hit and hope for critical chance. Unite with other girls cause unbalance and unsolvable since kasumi has her fixed rune. Camille stays just a so so character to me, not worth mentionning. What makes her better than Mace besides being early recruit?
-If Tengaar is enlisted, why not Lotte, they are pretty much the same.
And again, i think you're missing to mention several unite teams, unite attack is there to improve a character's usefuless,right?
-Varkas/Sydonia: early recruits, both can stay in back row or we can push heavy armored Varkas tank in front row. Varkas has good physical stats , possible holy rune holder, sydonia has decent str/speed/magic to support and initiate their awesome unite.
-Anji/Leonardo/Kanak: this pirate crew seems to never grab anyone's attention but they are actually good. All 3 may stay in back row. Leonardo and Anji have very good physical offence stats while speedy kanak may initiate their x 2.5 unite really well. 3 free rune slots at choice.
-Ninja team Kasumi/Fuma/Kage, they are decent statswise, speedy and have x2.5 attack together. All of them can stay in back row.
-Milia/Futch: Both have nice physical stats. both may wield shield, both are midrange attackers. Futch can start their unite quickly due to high speed. Holy rune for Milia, water/flowing rune is good for futch.
-Juppo/Meg: another pair for cover all tactic, unite to attack all in regular encounters then both can use trick rune in boss battle. Both are backrow fighters with decent stats.