New 1x10 project advice?

1. BJ are fine, as are Argos or Mercian
   
2. I would leave it alone, just don't fit the shifter wire, or replace left hand brake lever with a non-Ergo one
   
3. Rear mech capacity measured by combination of front and rear tooth differences. With single chainring, short cage mech will probably be fine but depends on rear cog sizes you choose.
   
4. Will look strange but should work.
   
5. Try it and see. Unlikely you can't fit Ergo levers, just a question of position.
   
6. You want a classic look? Get your wheels custom built at LBS, something like 32 hole, small flange, 3 cross spokes on shallow section rims. Mavic Open-Pros are good. No radial spoking, no deep section rims, no carbon, no aero.
   
   

Ps This was probably better posted in the bits and pieces or mechanics forum.