For G10 I use a 1/16" ball end mill. I use 3m 77 glue on a piece of MDF. Spray the glue on the wood, wait till it's almost not tacky to touch then press on. Set the router so that the ball part of the end mill is cutting into the MDF. G10 makes your tooling hot so using a ball instead of a square for that will make your bit last longer. I cut at 18,000 RPM and about 40-50 ipm.
For plywood, it depends on quite a few things like type and thickness of your plywood and the desired quality of the finished cut. Also depends if you will be using a spoil board (which I suggest). For softer plywood either a straight flute or down-sheer flute is going to be best. For the down sheer you will need to cut into your spoil board but a couple thousandths to keep the bottom edges clean. For harder ply like 7 ply aircraft ply you can probably get away with a straight bit for better chip removal because that plywood is almost 25% glue anyway. You also have to consider thickness of material cut. For instance you can cut thicker material with a small bit but you will burn the bit up quickly because the chips cant escape and heat will build up.
I doubt they make them in small sizes but for parts we cut with our business we use compression spiral bits that have both up and down sheer and we can hammer through plywood at 18-2000 ipm with a nice clean edge on top and bottom.
Hope this helps, but in other words, you will have to experiment a bit.