I'm kind of enthusiastic about this game, I think it has a lot of potential if improved upon, but right now my most pressing concern is the way various materials are treated, as straight tier upgrades from the previous ones. It goes Iron -> Titanium -> Naonite -> Trinium -> Abattium -> Urgium -> Xanion -> Ogonite -> Avorion, that's 9 steps during which the same gameplay repeats, you have to travel to a higher level area, kill friendly ships (?), steal their weapons/mining lasers, and then mine the higher tier of metal, to build a stronger ship to kill stronger NPCs.
Granted, you can probably burn a few steps, but that seems to be the general path laid out for you. I think that as far as upgrades go, 9 tiers is at least 4 too many.
Also, the way ships work means that you're far better off flying a huge monolithic brick than a detailed ship, because each block has it's own HP, and if it breaks, everything attached to it breaks free (premade ships are vastly inferior because of that). So far you can't sell metals or guns, but I hope this will get added to the next version.
What I'd like to see : the ability to build our own stations, some way to research, build and/or buy guns/mining lasers, more modules (like better hyperspace drives, shields, maybe tractor beams and more types of guns)...
If the planets were more than just backdrops, that would be great as well. I'm guessing there are some technical limitations to what would be possible, but even if it was just an abstracted menu where you manage planetary installations and the ownership grants you some sort of income, that would already be great. Maybe this could be done by building a special kind of space station (and you would have to destroy it in order to take over the planet).
Instead of infinite storage, I would also like it if we had a cargo hold block to include in our ship designs (and to stations). This way, trading and stations would take more importance. We can also imagine long-distance travel gates that would have to be built by players with large amounts of resources, so as to link rich core sectors and fringe areas. In general, I think that asteroid mining shouldn't be the best way to get resources, only the most easily accessible. Planetary installations should provide the bulk of resources, otherwise on older, more populated servers, there would be a risk of resource depletion.