I have a juki 2000 on a grace start right frame. I use the tension settings for normal sewing and using a 16 and/or 18 topstitching needle resolved all the problems you listed with the stritch length set on 0. I no longer have to buy the really expensive thread I was buying or adjust the tension for threads. I have used gutterman cotton and changed to Isacord poly without resetting anything. I do change needles often. I now fmq almost exclusively with metroemb poly. Love the looks and price is amazing.