I think we already discussed some of this over Discord, but I'll respond here as well.
A short, to the point but still funny intro was definitely a smart choice. I feel that's one major flaw with my own entry this year; it takes a while to get going.
Now that you mention it, I do get the Quake reference with the boss fight. I could never really get into Quake, was always more into Doom and Duke Nukem 3D.
The combat was definitely improved over Stalewater, so in that sense it worked out well.
It wasn't frustrating, but every feature felt a bit janky and kind of the bare minimum implementation. For example, you can grab ledges, but there's no prompt, it's not very smooth, and there's no animation. I wouldn't necessarily expect more than that for a small solo project, and for SBIG Jam it's not really a negative.
If there's one complaint it's that while the movement mechanics were fleshed out, the shooting was a bit more barebones. It definitely works, and didn't need more, but it's kinda weird to have a game with ledge grabbing but no reloading, sights, or alt-fire.
I think the revolver was the most generally useful weapon. The plungebow didn't feel that useful, I'm not sure if I didn't notice enemies being stunned or if there was a glitch. The stun-and-slam technique might be the key here, but I didn't use that and I'll get into that in a bit. The Tenderizer is hilarious and I'm not sure if I'd change it for SBIG Jam, but it is totally useless beyond melee range. The boomer grenades indeed sometimes didn't seem to explode when hitting enemies. I'm not sure if they weren't triggering because of a bug or if the hitbox just didn't match the graphics.
I realized afterward that the weapons had descriptions. I didn't use the weapon wheel at all because the number keys are what I'm used to and they're faster.
I completely forgot about the slam mechanic. I found it awkward and unsatisfying to use the first time, so never tried it again past the tutorial. I did misunderstand it, though: I thought you had to land on top of an enemy from above and only if the hit registered would you get explosive damage.
I can definitely see how the levels were intended to be longer and more complex. Even with the levels it has, the scope of this game looks insane for a week-and-a-half jam, so I'm not surprised they got cut down.
I think the biggest problem with this game, ultimately, is that expectations are going to be even higher next year.
Maybe getting the definition of Thesmothete would be a good reward for making it to the end of the game 😅