You know what I think the problem was? The orientation of the dip tube. I tore the keg apart, cleaned everything and nothing came out of the tube, put in cleaner, pressurized the keg and it was pretty much exactly the same flow rate. I gave the ball lock a 1/8 turn looser with the wrench and things started pouring normally. Can you have it too tight?
I'm thinking that the down tube angle was wrong last time and when I put it together as well and it was forcing beer through a small opening instead of picking it up freely. I may just take a 1/4 inch off the tube and see if that makes a difference but I sure saw that when I turned it slightly it started working.