Not impossible. I just completed the game. Once you get all the upgrades it's just a case of keeping your ship level and eventually you'll get to the end :)
The addition of Kreds upgrades has really put me off now. Don't like it when devs try and cash in.
The developer got a lot of support when he admitted he was new at developing games because the idea was so good everyone wanted to see him do well and improve. Even after the first update that went massively wrong people stood by him and gave him the time to fix the issues.
It's just a shame he's decided to cash in because all that good will is going to have pretty much evaporated now and he's going to have alienated everyone that gave him that initial support.
It's also a shame he's stopped posting on here because he was very active a few weeks back when the first few updates came out and now I've not seen him post in a long time.
Shame. Will keep checking back to see the progress of the game as it was an amazing idea that had a lot of support but until he removes the in app purchases I'm not going to spend too much time playing.