Printing a paper negative (or positive) gives a rotten result unless you like the paper grain and reduced contrast! I never work with a paper negative if I want high quality results!
As for exposure, well, working with a 35mm Ektachrome slide, enlarged to nearly full frame 4x5, I use about 1/2" at f22 for a 100 speed negative stock and I pull process to reduce contrast. I've done both color and B&W. With color, I have to use a Cyan + Magenta filter pack to get daylight balance for daylight color films, but otherwise I have had no problems. You will have to determine your own exposure based on magnification and enlarger.
For scanning, I just scan away and have made 8x10 negatives from 35mm and 4x5s right off with a slight tweak in contrast an density to match the original in tone scale. Pretty much the same as enlarging.
I have done quite a bit of both of these methods and have folders full of dupe negatives for use in my workshops. The reason is for comparison purposes. I want to be able to compare contact prints with enlargements from the same negative and this is one way to do it. It is also a good way to make B&W negs from good color slides or color negs.
I should add that to date, I have never been able to get a good slide digitally, but it works fine using analog processes!