I always found those perks useless with my 2H warrior on expert because the fights were over so fast, but my sword and board Orc on master takes much, much longer to take people down. Do you think the bleed damage perk - or any of the other weapon specialty perks - would be worth it?

None of them are really that great honestly.

Bleed and crit go off of the weapon's base, unaltered statistics. Armor penetration isn't too great because most if not nearly all enemies have little, or in the case of dragons and other non player race enemies, 0 armor rating.