Well, one of the big things to consider is the fact that those spells are a finite resource.  If we only end up with one big fight where casters can throw out all of their spells, they'll definitely feel more potent.  On the other hand, a fighter or rogue will never lose effectiveness, whether its the first fight or the twentieth.  Tactics are also a big part of it; if a caster is grappled (or swallowed) before they can get those spells off, for example, the chances of them being able to after that are significantly lessened.<br/><br/>On the parties, it looks like after the explanation you gave most people are a lot more ambivalent towards reformation, as it's a lot more dependant on the setting than anything else.  With that in mind, one other grouping that could work would be one based on the types of characters being played.  Given that AC, Sansuki, and myself are all looking at Underdark- themed characters, we could do an underground party and an aboveground party, which could make the party composition a little more coherant.<br/><br/>Just a thought, and I'd of course welcome other opinions, as its ultimately up to Ambrose.