One final thing (sorry for the spam of comments), it would be really very good if we could have multiple races rather than you and just a single enemy. The option on the map editor to have multiple enemies, additional races who are neutral to you (but may have gripes with other races) and allies. This would tie in nicely the diplomacy system you are mulling over. Perhaps introducing some multiple enemies etc on preset maps would also be nice.
Excellent to see you working with the people playing the game Momoguru. Also glad to hear a harder mode is in the pipeline. One small point, sometimes planets collide. If you add a bit of code which tests during planet generation if there is already a planet lying on that orbital, and regenerate the new planet if there is, it would ensure planets never get in each others way. It's not a problem which significantly effects gameplay, but it's the kind of extra polish which can make a difference.
Santa isn't that hard. First, do not use the laser. In my experience it makes the lance much less stable and actually makes it much harder to aim. Second, buy all upgrades and especially the lance and shield ones which you have to activate by pressing a and s. I forget thier names. They are a buy once item which you can then use in every run after that. Buy the stocking. Always remember to use the a and s upgrades, or you'll do no damage and get wiped out. When you're on a good run, use the stocking (press d at the 2seconds warning), and you'll do something like 60% damage if you're on target. Then just keep getting good hits with the a and s upgrades, and you should either beat him or just about loose. Within two or three tries you should win.
Great game, one suggestion. It would be nice if you could make it accelerate faster, sitting through the early stages is such a bore. Obviously if you were always able to do this you could get up to a high score more easily, so maybe being to accelerate faster untill you reach your own record would be good.