Spray baste takes a bit to get used to -- I think most people over spray at first. Read and understand your particular product, but basically if you can see it you've over sprayed! If you are having problems with your needle getting gummy, you've over sprayed. Usually you can just let the project sit out for a week or two and let some of the spray dissipate, but that isn't so good if you are on a time crunch.
I still use spray baste and have a couple partial cans remaining, I want to try glue but I understand that works better with warm and natural type batting than the poly batts I use. I typically will put in a few safety pins to hold things together until I get some stabilizing quilting in, but only a few here and there, particularly in the corners if I'm starting in the center of the quilt.
As Jennifer23 asked, how is this going to be used? As a wall hanging you will probably get some different advice than for a blanket.