Take Sleep for example, how do you adjudicate this spell and others which, in other editions have a defined Area of Effect?
IMC, we use the RC 40' area and since I don't typically employ a battlemat, I don't allow the spell to be cast as if there were hexes/squares. That is to say, that if the front line is engaged w/ a group of Orcs, and the MU hurls the spell into the melee, the combatants aren't glued in a static fashion in their nice, tidy 5' square. In other words, if the Orcs who are fighting your front row guys can be effected, it makes sense to me that those front line fighters could be effected as well.
I'm curious to hear how others work this out in their campaigns. Thanks in advance for your posts.