>I feel like the piercing railgun is fairly useless, as it seems to leave you unable to attack (and requires you to beforehand) for a while and only does the same damage as a single normal shot.
In fact it does double the damage of the regular shot. As I said, it's supposed to be an AoE option with less DPS.

>Enemies overall could also use having less health.
Current enemies are buffed and I added some new weaker basic enemies already.

>Also, please make middle mouse rebindable,
I should've made it more clear, but you can rebind it by rebinding "Zoom".

>I feel like it would be nice if the turret would start rotating once you look towards "the other side", even if it's not an "acceptable angle" it can rotate to.
Turret rotation gives me a lot of headache, but I'll try to rework it. I think you gave me a valuable hint on what to do here.

>Hitboxes feel a tad larger than they are, at least for the player's hovercraft.
Oh, hitboxes are a big mess and there's nothing I can do about it because of how they are implemented in GZDoom. Namely, they are square and do not rotate. I will try to implement some multi-hitbox solutions for bigger enemies, but this is gonna get janky.

>I think I'd make the dash work even if you're not holding a movement key, provided that your hovercraft still has some velocity either forward or backwards.
Sure thing.

>I've seen some enemies getting stuck for a bit too long on islands; maybe their turn rate  could be increased for a bit when that happens, or have them move in reverse?
I've reworked their movement code already, now they will stop, then back up and turn when they encounter obstacle. Doesn't really improves their pathfinding (if it can even be called that), but at least it looks like they're doing something instead of blindly ramming the wall.

>Stuff like hovercraft customization, swapping parts with stats or so, could be fun too.
I absolutely love that kind of thing, but I don't think it will be done in the current iteration. It can be done in GZDoom, but I'd rather avoid any feature creep on the current iteration, I want to release a finished game as soon as possible and focus on working with a different engine.

I don't think I will do proper mouselook in this version of game. That being said, I do hope I'll get around to remaking it on a proper engine later on, or making a sequel.

I have some ideas why weapons feel underwhelming right now besides the lack of damage. To address that I will introduce weaker enemies, and current enemies will be used more sparingly (although their attacks are much more threatening now), and you will see some indication that your shots are having  effect on them, like smoke coming out at lower health.

Finally, some actual feedback on balance and stuff. Also thanks for dunking on my ESL, although I'm not sure this is gonna be helpful since I'll be changing script a lot in the future.

>The dialogue box overlaps the selection box if the text is too long, and it barely uses half the width of the box before wrapping. 
Were you playing with a low resolution, or high scaling? Dialog box was kind of a mess at lower internal resolutions and I reworked it already.

>The turret doesn't take the dead zone into account when deciding which direction to traverse in, so it gets stuck if you aim to the other side too quickly or switch to the other side around the back.
I am aware of this issue and I'm looking for a way to fix it. By the way, enemies suffer from it too.

>I didn't have any trouble hitting enemies, but an indicator showing the turret's target rotation would still be nice.
I am planning to implement a laser sight or at least a targeting reticle.

>The railgun and torpedoes feel underwhelming.
Torpedoes I have buffed already, but railgun balancing is a tricky thing, it should have a lower DPS against single targets compared to regular cannon. I may increase cannon rate of fire across the board, plus I have already added a consumable item that temporarily buffs the railgun as one of its effects.

>One of the gray enemies at the start of level 2 remains stationary and doesn't respond to being attacked.
Did you "woke" it with a railgun shot? I know that it is one of the reasons for that happening and I found a way to fix it.

>Game crashed on level 2 shortly after I killed a supply boat
Can't do much about it without seeing a crash message.

>The delay before the supply boats drop their item is pretty annoying.
Fixed it, it does looks better if item is dropped right when the explosions start.

>Enemies have too much health.
Yeah, that's a problem because I only had time to implement one enemy type and hovercrafts had to fill the role of a basic enemy. Right now I am working on some smaller, weaker "popcorn" enemies while hovercrafts will have their attacks buffed to turn them into medium-level threats and they will be used more sparingly. That being said, I will probably reduce health on yellow and black boats.

>Enemy shots are too easy to avoid if you have enough space to not get surrounded, and the gray and yellow boats are too samey (if there's any difference at all).
Again, didn't had enough time to implement a proper difference. Right now the yellow boats are just souped-up gray boats (faster, more agile, more health, higher RoF). I am planning to add torpedo launchers on a yellow boat as well as adding more turret types. I'll try to implement leading shots across the board as well.