I just picked up OTC this week, and I've already logged a dozen+ hours. I love the game. The tutorial does a good job of introducing you to the mechanics of the game. However, even at that level the only practical difference between the starting companies I could notice was with the robotics. Highlighting the essential differences of the different company types is essential. And honestly, I don't know if I can tell much of a difference at the quick-play level. One of the problems is that the look and feel of the different companies is uniform. Except for the main base layout, buildings, factories, and mines all look the same. Functionally, it's easy to fall into the same gaming pattern every time you play. I think some cosmetic changes to the different company models may be helpful, as well as more clearly defined perks for choosing one company type over another. Perhaps start with a unique patent, or get one free claim of a certain type, or a discount on a particular advanced building. Basically, more thought should be given to making the different company-types feel like different company types.
Second, I've noticed that sometimes the grammar in the rolling news ticker is in error, particularly when it's referring to the player. On more than one occasion I have seen something to the effect of "You has received the patent on..." And speaking of that thing, it seems to take up a lot of the screen and not always be the most helpful. (I also dislike the pop-up auctions taking the center of my field of view). Would a CNN style ticker along the bottom or something be better and more in keeping with the economic theme of the game? That could actually make for a really neat gaming experience, if it were to feel like you were watching boring CNN coverage of mars development while you played the game.
Last, the end of the games seem to be anticlimactic. The closing data is poorly presented, graphically speaking, and the "You have been bought-out" lost scenario screen is both bland and incredibly depressing. There's something jarring, too, about losing a match. It doesn't feel like it has necessarily come to an end, just that you've been cut off.