Recently I've had cause to reexamine the way that combat rounds work one 2e. I've played with the Combat and Tactics 15-second combat round since time immemorial. However, C&T advises that spell durations be substantially reduced to fit with the new round time.
Thus, a spell that lasted for one minute now, in combat, lasts for 15 seconds-- fully 1/4th of it's original duration. This makes certain magics much less impressive, useful, or sensible. Why, for example, do they last so much longer when no one is fighting? I considered toying with an explanation based on ability to concentrate and the relative speed of casting, but that just puts a band-aid on the problem.
I'm not going back to 60 second combat rounds (way too long!) so I'm thinking of extending spell times back to their original length, that is one round of normal duration (one minute) would be 4 combat rounds (60 seconds). I'm not sure if this will make magic UNSTOPPABLY good (heat metal, for example) but I can't think of a more elegant solution. If anyone has solved this problem I'd be keen to hear about it.