Optimizing old meshes, advice needed (Blender)
 

I don't see any good reason to preserve UVs?

the original look is important

Good news: Found an error in our zone converter. Fixed it up and now it looks awesome: only one plain / surface for water / lava / etc.

This stuff was important to do, because if you want to swim you are to know what the water is, so we separate the water from the terrain for the FBX that is used by Unity.

Cool, show some pics if you don't mind. I assume you just remapped the UVs as it just looked like a repeated grid?

When I model any sort of terrain, I typically end up with only one uv map over the entire terrain in order to avoid clutter. Having to deal with multiple diffuse and normal maps can make things tedious when you need to make simple texture changes.

As far as water is concerned, it should never be a part of the terrain mesh itself (as you probably already know). I say this because water should be permeable (a player can pass through it). Modifying a single mesh's triangles to allow permeability on specific parts would take more effort than it's worth.

Oh and by the way, water UV's in EQ zones are very simple. They use a tiled planar uv map. That's it. The scale is something like 2:1 or 1:2 (AFAIK). But it sounds like you've figured it out.