Just like any pattern, it really depends on what you like to work with, and the look you'd like with the end results.
IMHO the smaller squares look so much more delicate, and intricate and show your work beautifully, and yes, more tedious. Whereas .... the larger are more clunky, work up quicker and because of their size don't seem as intimidating or are as difficult to work with.
You can even use smaller squares than the ones you mentioned. I've seen many that start with 1-1/2", so it's really up to you and what you want to do, as you can use any pattern, just change the size .... and of course, the fabric requirements will be affected.
Good Luck!!