Hi, Sam,
Looking at the pics, I think you are being too hard on yourself.
The fuzzies on your puzzle can easily be sanded off by hand, with a palm sander or with a mop sander.
The project definitely isn't too fragile like lots of fretwork can be.
The arrows on the last photo look like you must have let the wood come off the table surface and the blade
gouged the wood.
Other than that, I think the advise on some reverse tooth blades may help a lot with a steady feed rate into the blade.
God Bless! Spirithorse