Great work! I really love the level design on both iterations.
For the first version, you may want to do some level balancing as it’s a little too easy to kill the enemies and you can quickly outpace them. Maybe make the towers more expensive and/or limit their range.
You could also add some life to the scene by adding some particle effects around the bridge. Maybe try adding some water splash effects to really sell the river and also hide the tile seams.
For the second version, I really liked the UV glow-in-the-dark look. It gave everything a bit of a creepy ethereal vibe. The tree placement was also excellent and the layout really made me think.
I’m not sure if this was an intentional choice but, due to the camera angle, you can’t place towers directly behind the trees in the second one (the box colliders are blocking the tiles).
I thought this actually worked out pretty well for adding additional challenge though.
Once you’ve learnt about raycasting in the next section you could always come back and solve this if you wanted to.
Keep up the great work!
Great looking game, I like the Minecraft inspired style graphics