While I like the feat, why not simply make it more simple and more reliable.
1. Needs a spell that has maximum of 2 casting actions.
2. Add 2 somatic actions to remove a verbal action,
3. Add 2 verbal actions to remove a somatic action.
They want you to have the option so you won't ask for it, but they don't want it to actually work.
The Bard option works 50% of the time against a same level foe if you're optimized, which is pretty bad odds for the sort of things you're trying to get away with when you use this ability. The Wizard option is even worse, as you have to make two checks for almost all spells and those checks are never going to be optimized.