@Mercurius
If what you want is an old school D&D feel why not play BD&D or 1e? They're even re-printing a limited run of 1e in April.
Well there were lots of good suggestions already, but this particular issue is a bit of a sticking point. Fortunately, C&C and Savage Worlds both have supplements for minis combat.Mercurius said:I want a game that is more flexible in terms of being able to go back and forth between ad hoc/improv and tactical powers and maneuvers.
Thanks for the suggestions [MENTION=93857]C4[/MENTION], especially #2 - that's pretty much what I'm going for, although am not sure how to break the "stranglehold of powers."

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.