Ooh, very well done on this! Taking on 3D is always ambitious for a game jam, and I feel like you guys put together something that really feels like a complete experience.
Mechanically I thought it was pretty sound. I'm always a fan of tower defense, and this definitely scratched that itch. I wish I could've removed a couple towers, not even for resources but just to redo parts of my setup. I felt like the difficulty could've picked up a bit faster, but I only made it to wave 6 and the enemies seemed to stop spawning altogether, so I may have just not made it far enough.
Really enjoyed the music; that was super well done!
The UI/UX was all pretty clear. However, I'm stuck on a Mac trackpad, so scrolling to select towers was pretty painful. I would've loved to be able to select towers via number keys or clicking, but totally understand how alternate control schemes wouldn't be a priority in a jam setting.
Overall awesome job on this one!