Radiator, first. Then, swap to a 3g alternator. THEN go for the electric fan. Probably no major difference in cooling between the electric and mechanical fans, but your charging system will hate you if you go trying to put big loads on it with the puny stock 65amp alt still in place.
FWIW, there have been a lot of complaints on here about Black Magic (aka Black Tragic) fans ... not so much electrical fans in general, just that brand. You might want to look into a Mark VIII or a Taurus fan, instead - possibly cheaper, cools just as well, and easy to find.