My fuselage didn't have the holes drilled for the pins, so I was wondering if I drilled through the dimples wether the incidence would be good or if I would have to adjust the holes a little to bring it in check. I've heard other people say theirs were already drilled.

They are not drilled, you need to drill them. These dimples are for anti rotation pins which you can see in the photos. You use the copper tubing and glue the copper tubing into the wings.

I was thinking about leaving the canopy floor out, and I thought it would make it look like a bigger 33% plane or so, because they never put a canopy floor in them.

It's your plane, do what makes you happy. It's nice to be able to look inside it to make sure things are nice and tight. I took mine out after 3rd flight.

What do you mean by be careful with the 5645's? too much servo shouldn't hurt anything as long as there isn't any binding right?

Right, high torque/hi speed servos are fine, just be careful how you use them. I hope your using a good digital radio. When it's all ready to go we'll go over the numbers and if you do just what my settings are ... you'll be peachy keen.