you suck lol my first time through i had 9999 hp for damn near every character.
look for the legendary weapons so you can break the HP limit, and if you haven't dodged 200 lightning bolts make lulu's weapon. theres a merchant selling blnaks once you pass the thunderplains.
play some blitzball and become a god get jet shot 2, waka's legendary weapon, and his other 3 overdrives.
hit the omega ruin's. i'm sure theres some cheats here on VGC to help you with that.
it also sounds like you haven't captured every feind. theres a lot left for you to do and thats stuff is just off the top of my head.
when your done with all of that your HP should be well past 1k. my second play through has my HP at this point from 5k to 9k with Auron leading in HP, and i haven't even gone through the omeaga ruins yet. Waka should be the strongest pending on who's upgrade tree you go through first once you gone through his own.
if you need more info i'll be glad to help. i'm board lol!
send everybody through eachothers upgrades but don't give the girls the boy's powers and viceversa. the only exception is ultima which is kimaries move and drain form waka.
give those to special's to lulu and she'll also have them as overdrives. there black magic