There are some ideas in 4e that I like.
Rituals - I'm not too keen on breaking off combat vs non-combat magic into powers vs rituals, but breaking out some magical effects based on long casting time compared to short is an idea I like. If I were to adapt this to 3e, I'd be really tempted to design rituals with full effects and then make a spell version with short casting time that provides a partial effect of the ritual. I'd do something like the arcane lock ritual and a hold portal version as a spell in the normal spell progression.
Encounter powers - For martial characters particularly, I think the idea's a pretty good one. But I really don't much like 4e's implementation of these and how they don't really relate at all to dailies. Again, like with rituals, I'd design fighting styles or special maneuvers and give each one an encounter level and a daily level. The player picks which to use in combat at the time. This way, his dailies are at least related to the combat style he portrays in most of his other fights, it's just that the circumstances were right so that his practiced trick happened to do really well.
Treasure parcels - I like the idea of thinking in these terms when it comes to generating a fairly balanced, yet easy to build, loot pile. I'm not so keen on the way they "teleport" around to ensure that the parcels all get picked up. I just like the organizational structure in building reasonable rewards (that then stay put once I've placed them).
Free-form special maneuvers - Picking an attack stat and picking a reasonable defense is a good idea, but with all the effort in trying to balance the math around primary attacks vs NPC defenses, I think people will find that this won't work that well for any attack stat that isn't the PC's primary attack. Here, it's not the special maneuver idea, it's the other stuff going on with math balancing that messes it up. With the premium put on optimizing the primary attack stat(s) for powers, and defenses set to keep up with those, the other potential attack stats just won't keep up.
Stat bonuses - Ranged attacks getting Dex bonus for damage - good idea.