...thats what you get when you ask for people's opinions.
I agree with most of them - the CG is something you need to check once your plane is about ready to fly. It can be done easily without any tools.
For my bigger planes I have build my own CG machine, the smaller ones still get balanced on the finger tips.

So for your first plane you'll be fine without these, the deflection can be measured with a ruler.

For the glue - I build my kits with regular Gorilla Glue or Elmer's carpenter glue. Works great, even on the big gassers.
When you need more strength - on the firewall. landing gear and wing brackets - use epoxy and fiberglass.

I use very little CA, can't stand the smell and it's hard to get it off of your hands.