Thank you for a detailed review and suggestions!
I'll keep in mind your laser suggestion, although I'm not sure if it's currently possible due to engine limitations. The duration of the cancelling effect in particular is currently not possible to change sadly, it can only be toggled on or off. I haven't gotten feedback on ship speed in particular so I think most people are fine with how it is right now, but I'll keep your feedback in mind. The engine will soon get updated to allow focusing like in touhou for slower movement and I'd like to experiment with it so speed change may be necessary.
The scoring behavior you described is not intended, the score is supposed to be reset on death and not add up each individual credit score. I believe it's an engine bug which escaped my notice. I'll troubleshoot it with the engine developer after the jam ends.
Glad you enjoyed Stage 3! It was my favorite stage to design and a lot of it was experimental stuff which I hoped people would find interesting. Stage 1 boss in particular was the very first boss designed when I didn't know how exactly the game will play out, and some other testers have also expressed that they have had issues with him. I will look into ways to rework him later on, as well as his ghost ship version's patterns which might be a bit too tight right now (but hey, some extra more points for keeping to the "confined" theme!)