A very solid mission, overall. One thing I noticed about this mission (and your others) that all too often gets taken for granted is the layout of your galaxite. Few things in level building are as much of a PIA as adding galaxite. Lots of times mission authors (myself included) will do a cut and paste with a single glob of galaxite, and the result is a somewhat "gridded" look to the mission. Yours had a more natural spread, and that, combined with creative terrain layouts, adds to the overall
feel of the mission, making the terrain seem wilder and really making you forget that you're playing a game. Good job!
A couple of items by way of feedback:

Omni never left their base to attack me, for some reason. I don't think Omni's unit groups are being built until the 25,000 credits are mined. By that time, I was already down in their base and saw their vts and hrc begin making units - right before I destroyed them.

Taking Omni's base involved some real close-quarter fighting, and that's always fun. One thing I noticed, however, was that Omni's units that were guarding the base were clustered together by unit type. So when I saw that I was up against a knot of Hydras, I backed out and sent my Rocket Troopers in and made mince meat of them. Liberators had to face the combined might of my Hydras and Cyclops, and Troopers were mowed down by my Liberators. Maybe in tight quarters they might be better off if you mixed their units up a bit. Also, their agressiveness was set to guard sight, right? You might want to make it pit bull, since they would let me back up and regroup, and that is definitely something you don't want.

You might want to place a surveilance center in the extreme right of the base, as I'd destroyed both by the time I got to the bulk of your towers.

There were some Omni units beneath the mini-map, and had they not fired on my troops as they passed I might never have finished this mission....

The river crossing makes for a niice little choke point. If you really want to turn up the heat, place a good mix of Omni units on the other side to greet players as they cross.

I loved the narrow entrances to your base! A few Omni units guarding them would have made it almost impregnible! Great base layout!
Keep up the good work! I look forward to your next mission!