Oo0o0o I like those combos. I would love to use Aeris, because her limits are great, but I don't wanna waste time leveling her up. However I haven't played ff7 since I beat ff12 a couple times, so I have since become immune to the tedium of leveling up and in the case of ff12 loot hunting/LP farming loll.
I definitely agree that Yuffie is essential. Her limits just kick ass, and she is very competent with materia and attacking. A lot of people don't like to use the female characters because they have "lower vitality" stats and get hit harder, but I never noticed that, and if anything a Touph ring fixed that...plus with Yuffie she is a back row character so the damage thing is a non issue.
I like barret, and cid, but I will def. agree that their limits leave something to be desired, except for Cid's Highwind, and maybe Barret's Ungarmax with the right weapon. Vincent's limits however don't bore me, I esp. love HellMasker, so I often use Vincent