The quilting aid I use the most is a 5" x 10" ruler by Kimberly Einmo. Since I sew with lots of pre cuts, that ruler is the perfect size. Lately, I have been making blocks with lots of tiny pieces (e.g., a 12" block with 100 pieces). The small ruler is perfect.
As for the Clover clips, I love them. I bought a small package of 10, I think, and was not too impressed; but later, I was able to get 100 for half price. Having enough clips for the entire quilt really made a difference. Now, I always use them to hold my binding in place. I wonder now how I ever did without them and can't believe that I once didn't like them.