I agree with Stephen. There is nothing about this negative that should cause undue problems. I definitely has sufficient exposure, and after looking at it again, and Stephen's inversion on a better monitor it doesn't look contrasty either.
Something strange about this enlarging issue. 75w was always one of the standards in so many small/medium format enlargers. I used an Omega B66 for years with a 75w bulb and often made prints smaller than 8x10. Never had a problem.