Hey silversatyr, thanks for the feedback and the Youtube play through! Seeing someone else play shows me things that I couldn't see being so close to the project.
As I have mentioned in a previous comment, level design / level layout isn't my strong point, but I do believe that with each game that I make that I get a bit better, plus feedback such as yours points me in the right direction.
Also, other basic game design things I have to remember for the future is to add a how to play or how to control screen, probably during the loading screen or splash screen. The jump and you die bug I never encountered, so thanks for spotting that for me. Also, I didn't realize that the coin counter reset after 100. I added the extra coins to try and "pad" the length of the game. I also agree that the game could have used some sort of in-game back story or explanation for the reason why you kill bugs and collect coins. The size of the levels vary from small to large, so coming up with a good traverse speed is a bit difficult, but something that I'm sure I'll get right in a future game. Finally, about the difficulty level, I did want the game to be like an E for everyone, and I wanted my 3 year old daughter to be able to have a relatively easy time playing it, but I agree the challenge could have been ramped up.
Thanks again for the feedback! Hopefully a future game will be a much better example of a proper 3D platformer!