Got to lvl 6 with a score of 137574, mostly holding onto my EX for survival. I did level 5 in practice mode until I could do it a few times in a row.
The design of this game is so, so smart. Using the bat guys as a resource for canceling, planning a route to the repair system, doing little tap dodges to avoid the aimed shots in the cone of bullets the skull guys create, and manipulating the cross gun ships... I could go on. it's really awesome and it does so much with just a few enemies. It's so elegant I actually don't know where you would start to come up with something like this.
The bosses have a lot of character despite shooting the same pattern with different parameters (until you get to level 5 where it adds an extra shot.) The level 3 boss is particularly memorable. It allows you to stay a lot closer than the other ones. The boss sprites from Helicity are really fantastic too.