It certainly wouldn't hurt to remove some models and simplify some structures. In some places there are models which you can't even see unless you're trying to rocket jump out of the map, or looking from a corner of the map that nobody would actually use during gameplay, and some of the "detail bays" ontop of buildings seem unnecassery since they're way above the players normal FoV.
An example of this is the building above and beside CP1, stage 1. There are crates and doors on a bay which can only be seen by spectators or someone rocket jumping whilst looking away from gameplay, and windows and "extensions" that are only visible from the back of the CP where people never bother to stand. The building could have a third of the amount of detail you've given it and people probably wouldn't even notice the difference.
Another example of excessive/non-focused detail is the pond on one of CP2's flanks in stage 1. I played Zink about 50 times before i even noticed that and only because i was spectating and caught it from an odd angle. There are a lot of models, not to mention the water, adding to your file size that are visible from a very small FoV, and a FoV that would never practically occur during actual gameplay. It should either be as visible as possible, have less detail or not there at all.
The map's beautiful but perhaps too much focus has been put on the beautification of the map in general. There should be areas of focus detail so parts of the map can appear to be more important than others, instead of the entire map just looking like one big detail scene. Ironicly, when i look at some of your buildings i think they could do with a few bare walls.
Cutting down detail like that would certainly also reduce the amount of content lit, and thus light data.