well as you can see i have 16bard/2ftr/2bbn, and i do use otto especialy in epics since dc is youre preforme and not youre cha mod + lvl of spell....
you need base of 17 preform iirc (without item) for AC song. [by otto i mean otto irrisistable dance - the one on touch not dance ball
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If you go dps part do you plan to go Warchanter, spellsinger or virtuoso ?
On swithcing to 2wf do you have wepons on you you are aware you sohould then craft 2 min2 or get 2 boss beaters, if you have min2 falcion i would stay 2hf
As for bbn part 2 bbn give you +4 hp over ftr, power attack enhancment barbarian constitution 1, dr 1 (1 more rage if you go WC 1 rage enhancment and enhancment for 25% longer rage) remember if you go bbn you dont need to be raged all the time
Feats power attack, improved critical: wepon choice, toughness, greater style fighting - this are 6 + 1 for youre PrE + quicken + extend (if you go human youll have 8 feats + 2 ftr feats) so 1 is empty you can get stuning blow sf or empower healing