Three slice mode felt like a chore to finish before you could get to the fun modes where you don't have to worry about meeting a certain quota to be allowed to try the next level. Fun after that though.
I would really like the ability to have a checklist of block types available and be able to turn some of them off. It gets frustrating when there are too many block types to be able to use them effectively.
I love the fact that the advertising is done passively in the background instead of where it would annoy you (the ship being painted with "Positech Games").
I'd appreciate some more interesting node maps (e.g. some nodes connected to more than 2 others). After the first few tutorial levels, you only ever get a 'cycle' structure so it never matters which particular node you place in a position at the start.
The movement feels clunky becuase you can't stop between grid squares (this makes it easier to tell where your blockbeam is pointing). Once you realize that, movement isn't so bad. Good game, but it needs more tutorial because it's really hard to tell what you're doing at first.