My warchanter bard is always in the thick of melee, that's why I built her.
It's really hard for bards to give eachother advice though, as we are all so different. That's what is great about being a bard!!! For instance, my level 10 spellsinger is sitting on just over 110 hp right now...ya...she hides in corners a lot :P
Any warchanter that expects to melee (which should be all of them) should have a starting Con of at least 14, preferably 16, minos, greater false life, and be working on an HP item. I'm sitting a little over 450 right now and still have some gear to grind. Should be able to make it to about 500.
The main problem I find with lightweights going down in Shroud is lack of heavy fort, not hit points. Although hit points can also be the cause.
Spellsingers can dish out damage from a far as well though if you pick up a heavy repeater. Every build is different, so figure out your limitations before you jump in.