Mining seems to be the most profitable of anything I've seen.
Trading can get you a good profit if 1) You have a huge hold, 2) You do tons of research and watch lots of data to find good routes (as they seem to constantly be changing)... I don't have 1 and don't want to do 2.
Agent missions take alot of time... 85% seems to be on autopilot. I spent the last three days just doing agent missions... pick up three or four, build a jump list, then jump. Go play with the dog or wife or watch a movie/football, then come back every 10 minutes to dock and drop-off/pick-up. Not much of a payoff, but relatively easy to do without much attentio
With Connections 2, I've gotten into the Level 2 agent missions, which are paying much better. It seems that once you get up towards level 3, the payoffs are really nice (akin to mining)... but the missions are much much harder... barely solo-able with a Battle Cruiser.
So... you pick. Realtively boring with lots of payoff (solo mining), Tons of attention with lots of payoff (trading), or small attention with mediocre payoff and good status benefit to the corp (missions).
Of course, if you just want cash, drop $20 and buy some ISK.
