Re: All Bards. Tomb of Horrors. What could go wrong?
Besides touch of healing, take wands of lesser vigor and healing belts, maybe some wands of summon monster I. Get other magic items to duplicate other things. In ToH, combat isn't as big a deal. I'd recommend getting a few scrolls of greater planar binding, to summon Tulani Eldrin (they have at will cure moderate wounds, telekinesis, Empowered Chain Lightning, at will, as well as Power Word Kill 1/day to get rid of some of the weaker monsters, permanent true seeing to boot, and to top it off, they have 18th level bardic music abilities and Words of Creation). Maybe a few other outsiders with casting as well.
Tulani have charisma 26 (a pit fiend has the same, so it is reasonable to expect everything you'll want won't have a better modifier), so you'd need to have someone pump that, though Improvisation (CAd, bard 5) gives you +5 at CL 10, Charisma at least 20 is to be expected, using blinding beauty and eagle's splendor could give you another +9, Guidance gives +1 and it is reasonable to assume that the Tulani would want to, so you'll probably succeed.
Remember, just because you'll all bards doesn't mean you have to go in singing, ToH has no random encounters so you'll be able to rest whenever you need to, this means that going nova if possible on every encounter and then resting is very viable, and investing in a few times/day items can be worth while, and traps are set off just as easily by celestial monkeys as by 20th level fighters, so investing in a lot of low level wands will pay off (take speak language to speak the language of some creature that can manipulate objects, pull levers, etc, so you can have your monkey pull the obviously trapped level [and lever] instead of you).
ToH has a reputation of being lethal, though in 3.5, it really isn't as lethal as some people say it is, so long as people don't blunder forwards without stopping to look and check first, and with 3.5, you can do that indefinitely.
Thank you to SubLimePie for my wonderful kobold cleric/wizard avatar!