I noticed in that poll Hana was very unpopular as a 5th character! I just wanted to say that she was my favorite because:
1. her sprite was very unique, and very recognizably styled(I thought Ki looked like a potato/rock creature at first sighting)
2. her attacks where mostly amusing and useless, making the player's main party less reliant on the typical tank like 5ths which came before her and who come later in the game.
3. her storyline was probably the best of any NPC in the game, aside from Dad's due to sheer epic Guardian-isms. Hana had a personal goal and a main antagonist. A main antagonist who drops the Abacus! I credit Hana for that.
Also.. for an extra treat... try taking your pet dragon to the Micron spawn point. Leave you're dragon in that room and you'll find Hana winking at you! HANA IS MORE THAT WHAT SHE SEEMS :O
Hana may not have overkill stats, but by first world standards, she is still a tank. She has much better agility than strength, making the Rapier a dangerous weapon in her hands. Her defense is 11, so nothing except the Rhino can do any damage to her (9 is the top end you can equip with humans and mutants, making most attacks except from Jaguar and Goblin do nothing, and she is 2 points above that) Her magic is a great asset, though I would reserve her spells for times when you actually need them, rather than wasting them.
She's still a tank, just less obvious.
~ Kuro-chan. http://www.youtube.com/watch?v=rTYpKlIc_fg <- Everything you need to know about DLC nonsense.
I find Lynn to be completely worthless 5th character. Like BareknuckleRoo said, she exists solely to be rescued. Her original weapons never do any real damage. Maybe if you let her kicks etc "level up" she's worth a crap, but you never have her long enough to do this, unless you grind.