I think, what making mod-game Jazz will help to spent our time for waiting JJ3 (Coming not soon!). But the best mod will be on Unreal Tournament 2004. Nice engine, maps and fx. You can set a gore level = 0 and create a jazz, spaz, lori and other models for this mod with you own blood style (each model have it) and create a style like NoBlood with empty textures. Create weapons and pickups and more, more, more...

Just install full version of UT2004 - it includes Unreal Editor 3.0 to create mod.