What a great question, and no 'right" answer. I agree with everyone who says starch, press, and trim as you go. Label, label, label everything you've done. ("Trimmed", "To be Trimmed"--and keep all of one kind in a ziploc bag inside a box with a lid (also labeled with the name of your project). I like to sew 10 at a time, starch and press 10 at a time, as the mood arises. Definitely would not suggest working with more than 20 at any stage of the quilt.
Keeping similar color units together will enable you to see what you have at the end, when you're ready to hit the design wall. Then you can spread them around "randomly". (If you're anything like me, "randomly" involves a lot of work--I mean play--to get it right! Harder than non-random any day!
You'll also know after 200 if you want to keep going toward 2000. If you have blocks pressed and trimmed, you can decide at any point when enough is enough. You might make it 2000 or you might grow weary of it. At least if you grow weary, the bulk of the task will already have been done.