One major improvement is the AI. One of the team members took out my old 'run at the player' ai, and replaced it with something more flexible, that has the ai alternately hiding and coming out to shoot depending on its aggressiveness, etc.
Much more tough & fun now.
I've fixed a ton of bugs, including a nasty animation corruption issue, and a mismatch between the world bounding box and the rendering bounding box.
I've made a separate bounding volume hierarchy for physics objects vs visuals. Most entities ( like the player and enemies ) are added to both BVH trees as they move around the level. Things like corpses are only added to the visual tree so they don't waste any time being processed for collisions or raycasts.
This also fixes an issue where a character's physical bounding box was always a 1x2x1 meter box, but his corpse is more like 2x1x2. Now the true visual bounding box is used.
Weapons now appear in the character's hands as well, which is a nice change.
Here is a recent shot of the temple level at 800x600 with 4x aa applied.