Ok so a bit to unpack here.
1. A shed is pretty easy to build, especially if there is no permitting/inspections.
2. A shed is pretty cheap to build, I mean its just wood, and that stuff grows on trees.
3. I dont think you need detailed prints. As you want to build this custom for your uses. You want the window where you need it, the door where you want it so you can do X Y and Z in the shed. They are however a really good starting place and a good guide if you get stuck. They looked good to me.
4. Having a good foundation will be the biggest issue, so be sure you get that right, you would hate to be having an error in the foundation effecting the whole build the entire time.
5. 100% run electrical, I would say run at least 3 20 amp circuits. 1 for lights and 2 for tools
6. I think your hardest part is going to be framing the roof out. Take your time, get the first 1 100% correct and use it as a template.
If you have any detailed questions I am sure we could help.
Good luck!