What is the guildline (if any) or your guideline...
for example. Take Resist energy. For a one level hit they made it communal. What if you wanted to make it still single person but instead of 10 min/lv, make it 1hr/lv?
I realize there is the extend spell feat but really...okay now I have 20 min/lv? It is all the same.
Now I realize that certain spells can really get broken if you allow them to last all day. Spells like blur or haste or similar but what about those that arent game breaking?
I mean face it, it is an economy of actions. Now if you have an encounter where you get to buff for 4-5 rounds before kicking down the door...thats all well (and the fact that a good DM just makes the BBEG disappear for 10 minutes then come back when your buffs are gone...) but for the instances that you turn the corner and you are slap in the middle of go time....it really sucks when you have to spend three rounds buffing just to survive (in the case of a wizard).
Seriously, think of this. If your party encounters another party of NPC adventurers, who do you target first? You go after 1) wizard or 2) healer. So the poor wizard in the back gets zapped the crap out of by anyone with any amount of ranged weaponry before he can go. And at d6 hps + traditionally low con it means dead wizard before he can even cast anything defensive (we arent talking about contingency level wizards here).
So what are your suggestions?