referring to Velocity and gb/fb as secondary, so I'm assuming Control and L/R are the primary ratings to look at for pitching. with that said what would be some good guidelines when looking at free agent pitchers? (ex. control 50+ L/R 70+ etc.)

They all work in conjunction with one another.   Concentrate on control, VR, VL, P1 and P2.     I don't set minimums because other ratings can lift a pitcher and the ballpark/defense also plays a big role in how effective a pitcher can be.   That said, I've never seen a pitcher with 27 control do well nor have I had much luck with sub 50 splits.

You can find some bargains if you're flexible on "minimums" as Mike said.  I don't expect this magic to continue, but it appears  Hardball Dynasty – Fantasy Baseball Sim Games - Player Profile: Trenidad Paniagua is going to be servicable if not pretty good in my ballpark even with sub-50 splits--he was let go for nothing and nobody signed him in FA.  I've had reasonable success with others like him but if splits are in the 50s or below he has to push mid 80s to 90+ in all the other "primary" attributes.  I would say the same thing for low control guys.  You can live with a 40 control if his splits and pitches 80-90.