Top 10 characters, eh? This'll take some good, old fashioned thinkin'. Oh, and Faris is the Pirate in FFV. *Avoids spoilers*
1) Black Mage -- Come on now. :P Black Mages have been my favorite class ever since I've started on the FF games. Wow, it's been almost my whole life. Anyways, sporting the Mysterious Hat and Cloak, and mastering the dark arts of magic truly creates one awesome character. Thank you, Amano.
2) Aeris -- Yeah. I liked her a lot. I know, I'm not one for the newer FFs, although FFVII was very good. But Aeris, she was compelling. I liked her a lot. And as awesome as Sephiroth was, I was happy to unleash an Omni-slash on him at the end. Jerk.
3. Cecil -- Dark Knight or Paladin, Cecil was pretty darn cool. He was wicked as a Dark Knight, and I preferred him that way. However, I didn't complain when the change took place. I grew tired of doing 1-10 damage to undead, anyway. Besides, he has Rosa.=F
4. Kain -- Although he double crossed me so many times, wait. No. Not Kain.
4. White Mages -- Who's the trusty helper (Preferably Female) who's behind every Black Mage? Well, it should be a White Mage. Actually, I'm not a fan of the Male Priests, as they seems kinda, well, let's just say I think Females are better suited for the job. Oh, the irony when compared to real life.
And yeah, I know I'm not picking specific characters, per say, but I think I can get away with it, thanks to FFI. That's not to say I like ALL characters of the class, no sir.
5. Sephiroth -- Lance Bass' voice, I guess it wasn't too bad. But that's not really Sephiroth, now is it? I didn't like him an awful lot in FFVII, whilst playing through it, but after Kingdom Hearts, he seemed so much more, uh, cooler? Yeah, having the Masamune helped him out too, I guess. I'm glad I got my revenge, in KH, too.
6. Cloud -- Jeez, I'm such a hypocrite. A lot of these characters are from the "New Age" of gaming. While I still prefer the elder games, I will admit, FFVII had great characters and a good story. I guess it was the exception.
Cloud was cool. A liar, but cool. Maybe not a liar, well, yeah. His KH costume was cool, too.
7. Orlandu "Thunder God" Cid -- While making FFT a very easy game after acquiring him, he was very cool. Two words -- Lighting Stab.
8. Kain -- Never mind. I still hate Kain.
8. Celes -- Yeah. I'm not a Terra man, although, I didn't mind her. Celes floated my boat. Runic would effectively make me extremely happy and very angry at the same time; I'd use it to suck the Enemy's Magic down the drain, while forgetting she'd steal my Cure spells too. Man, that'd make me so mad sometimes. But yeah, I like Celes. 'Nuff said.
9. Lulu -- I guess. I was trying to avoid FFX. And I'm Positive I could find another two characters to knock her out, but why not? She's calm, collected, and a Black Mage. Not to mention she's a looker, too. :P
10. Kefka--Cid Highwind--Rosa Combo -- I could decide. So sue me. If I honestly had to pick one, I'd say Rosa. But then, Kefka was strangely cool, and had a pretty darn cool Boss Battle theme too; Dancing Mad. And Cid, well, come on, it's Cid. With a line like "Shut the 'heck' up and drink your 'Gosh Darn' tea.", how could you not like him? Really.
That about sums it up. I'm sure I forgot some that would knock others off of the list, but meh, it happens. It was more difficult than I had anticipated.