Please no magical music note-plosions...

You can have a valuable Bard without them being a summoner of weird light-refracting/air-distorting sonic magics and if a mage were capable of the latter they probably wouldn't waste it on anything as indirect as song. It makes no more sense to take a Bard's weapon away from them and have them make do with their utility perk alone than to take away a Paladin's sword or a Ninja's knives in favor of pure defense or stealth+Ninjutsu respectively.