Here are a couple of tips:
Use large diameter shallow containers vs small diameter deep containers to extend the pot life of polyester resin. epoxy is less sensitive to this.
You will get better results with spraying pva by not thining it and spraying with a non hvlp gun. The best pva gun I had was an old binks model 7.
Tape down some heavy plastic over a table and lay your cloth flat to wet it out then pick it up and place it in the mold. On choped and thicker cloth pour/paint some resin on the plastic before placing the cloth on the table. Large pieces of pre wetted cloth can be transered to the mold by rolling or folding up the cloth to avoid streatching and distortion. Doing this will speed things up and can help reduce resin pooling in the bottom of your mold.
Tap Plastics in California is a great resource for all things composite. their house brand of epoxy is very similar to system 3. In addition to the 3 hardeners having different working times the most important difference is they produce 3 different levels of stiffness.