Take a look at the perfect sewing table I found...
#14
I have one very similar to yours, also a computer desk. The tray on mine is adjustable so I can set it to the height of my sewing arm. The not so good thing about mine is that the cut out is in the left position. When I need extra room on the left side I just move two rolling drawer sets in beside the table. It works for me. I don't have an acrylic table for my machine but the arm of it butts right up against the side of the desk so I sill have a same height work area. I'm going to check out the info you gave and see if it would be affordable to change out my table. I got mine at Walmart years ago for around $100.