I've been working on a dynamic tile-based culling system.  Has the benefit of better performance, better RAM usage, and will support Citadel's ultimate and as yet uncreated feature.  It's a long planned thing, involved, but necessary for the things to come.

Also poked at adding support for custom music mods that people could drop in and use to override one or all tracks, but it's not quite ready yet.

Not much progress these days with my current setup and playing with my 3 kids, but still going when I can here and there.

Dynamic culling seems to be working quite well now.  Already a decent performance improvement.

Ability to load custom music is finally in.  Just need to do the tedious part and link the override system to each dynamic music snippet.  I also plan to have two types of overrides, snippets and looped where the dynamic music system does not do anything if looped is picked and instead it just continuously loops a provided mp3 override that way any custom mix ever made could be dropped in and used as is.  Or any mp3 music really.  Or .wav.  Haven't added support for midi + soundfont yet though but that's planned for later.

As a bonus performance improvement, perhaps you could use normal mapping for further geometric detail so not as many tris need rendered?