The interesting project. You are the fan of game "Elite"? This information window (
screenshot) is obviously borrowed from "Elite 3: First Encounters" (window design, text colors, data about star system).
It is a pity, that in game there are only two dimensions (in space). But there is a 3D-action component. Here game is similar to games of Derek Smart (Battlecruiser Millenium and Universal Combat).
Unfortunately, the surface of planets almost always looks deserted. Only textures are different. The walk in desert is uninteresting. There is not effect of walk. Movement is very slow. It would be desirable to see more details, more objects (grass, trees, stones, city structures, the transport traffic). You can reduce 3D-world scale. You can also improve the component of surface combat or let the player make peace walks.
The 3D-Action component is pleasant addition. But I think, that it is a unessential part of game. All the most interesting happens in 2D-space.
You should refuse 3D-action or alter it. Make 2D-action.
It is only the recommendation. Simply consider this, when you will begin the next project. I hope, it will be space game too, with three dimensions.
If this game was free, it could forgive much. But "Cold Dawn" is shareware. People do not forgive defects of such games. Be cautious.
Nevertheless, greater work has been done. And it is necessary to pay for this work. But your game already has many worthy competitors. I wish you good luck in your business.