In my opinion a stock block can't take more than say 400hp on a regular basis so you don't need to worry about a "supercharger friendly cam;" A stock cam will do just fine for 400hp.
1) Will a centrifugal supercharger put strain on the crank nose---i don't know; Small block chevy crank noses CANNOT take the strain of a roots type blower. (not sure about the smaller ones though---144, 177's etc.)
This needs to be researched first and foremost.
If you want to go roots and are happy with around 400hp/450tq then i would at the very least be looking at a forged crank with a larger nose----such as what scat offers. Personally, if i was going to go all that way, i would also be looking at a hi-po block such as bowite or dart; This way i can just crank to boost up to get 500, 600, 700 etc. ponies.