I'd suggest the Bitz jig. It an do everything you need to do. You'll probably have to get a few different clamps and nocks for it though.

As far a helical/offsets/ and straight are concerned:

If I am fletching using feathers, I normally use a helical. It doesn't matter if you use right or left on a compound. Some say if you use right it will tighten the point on impact. I use a left, and never had problems.

If I am using vanes, which is what I use for my compound, I use an offset. I don't like to use helical on vanes because of the vanes memory. They become difficult if you do not allow the glue to dry enough before removing the clamp.Some people like helical on vanes though. I nver use a straight fletch, because if I am shooting my compound I am using fixed broadheads. You will get a little stability on the arrow if you use an offset, you will get the most stability if you use a helical. But remember that the more drag that you create on the back of the arrow, the slower your arrow speed will be.

How much offset or helical: That will depend on your arrow rest especially if you use a prong style. You have to make sure that you have clearance. I believe that there is a point where you can have too much helical also. I believe that if you look down the arrow from behind, the fletchings should not overlap each other.

Best of luck to you!