Should there be more metamagic limits?

[Mystify]

The vast majority of truly agregiously broken casters rely on using metamagic to boost their spells to higher levels than they could normally cast. This is why incantrix and anima mage and the like are so absurdly powerful. If you add in the simple rule that whatever metamagic cost reduction you apply or free metamagic you obtain(with the possible exception of metamagic rods), if the spell slot normally required to cast a metamagiced spell is higher than you can cast, you cannot cast the spell. Metamagic reduction and free metamagic would still be powerful, as it still lets you prepare high-power spells in low level slots, but you can't use it to cast a spell that you would normally have to be several levels higher(or epic) to cast. Divine metamagic would be useful, but doesn't allow you to cast a persistant spell until you could normally be able to cast it. The cost reductions become spell slot savers, not max power boosts.

Thoughts?

[Aspenor]

I'm pretty sure this a fairly common and effective house rule. Nothing wrong with doing it at all.

[Divide by Zero]

This is already a part of the bardic music metamagic reducer by RAW, and I rarely see any discussion of that being overpowered, so extending it to other methods seems like a perfectly reasonable house rule.