Bug HLG

I think I will try to make the parts myself, since this will be good exercise anyway. I would appreciate it if you can give me some pointers, since this is my 1st scratch built (I fly EPP slopers). I actually have made 1 set of wing but I am really unhappy about it so I am going to remake it. The problems I have encountered are: 1. The notch for the LE dowel - how can I cut this accurately? Inaccuracies have led to the dowel not sitting on the same horizontal plane) with the spar (is this normal?) and one of the ribs needing some lengthening for it to reach the LE. I presume if properly made the LE, spar and TE will lie on the same horizontal plane? The crappy wing set I have is obviously twisted. 2. The root rib dihedral angle. At first glance it appears simple but once the two wing halves are made the two sides don't seem to meet each other too well. I tried to sand the root rib with a block / bar sander but really the results are not too good. I wonder what are the tricks necessary to achieve a perfect wing joint with the right dihedral. What's worst, when I was trying to sand the wing halves I manage to damage them - hence new set of wings needed. 3. Related to 2 - I guess problem 2 can be solved if I can cut correct bevels top and bottom of the root rib? But how can that be achieved? 4. Wing center sheeting. Because of W1 being slanted the sheeting does not want to sit flat esp in the front part. 5. It may sound silly but how do you keep the ribs parallel during your construction, esp during the LE glueing? 6. What tool do you use to cut that perfect lightening hole in the wing tip? Also would a laminate of 2 1/16" tip works better than a single 1/8" tip? I think if I am not too picky most of the above problems will probably be ok as long as they are symmetrical, except the center wing joint which I just cannot get right! Thanks for any suggestions Henry