it is easy to get lost, an arrow pointing to the portal when it is out of sight of the radar would be helpfull.
maybe change the repair tokens to scrap you can collect and use as a currency for repairs and other things
otherwise, great game. the ability to upgrade modules could be cool.
different types of weapons (missiles and as a counter point defence, a hangar bay for drones)
larger varieties (2x2 etc) would be interesting. maybe you can merge the blocks you have together into the bigger variety