Cleared the tutorial level. There are balance issues for sure — the melee characters have a huge handicap, and there's no benefit to attacking enemies at close range. When the boss with the purple bullets showed up, I pretty much just stayed back and dodged left and right. She was off-screen for most of the fight (probably should make the boss room smaller).
I also couldn't figure out what to do with the umbrella dudes. There's one point where you pick up a key, and a huge umbrella thing bursts in and blocks your path. The tutorial tells you to pause and click respawn, which is what I did, but it still felt like the enemy was a midboss and not just an invincible obstacle.
Balance aside, the scope seems huge and there are a lot of interesting directions you could take this. I didn't notice any bugs, so all you really need is more enemy variety to force the player to play in different ways. Would be cool to have an enemy/boss that can reflect your bullets to discourage spam.