Those look nice. However I guess I am not following your idea with the placement of the brackets. I figured you were going to have something attach to the top horizontal bar and extend over your seat, that way it would provide shade and keep the rain off you if it would happen to rain while you on it.
Also did you use a plasma cutter to make those brackets? They look clean
I tried using an umbrella on my 2310. I zip tied a pvc pipe to the ROPS and put the umbrella in it. The first good wind caught it and the brush hog finished it. If you use the umbrella, make sure it's secured very well.Next time someone is tossing out a deck umbrella on CL, snatch it up. Those can be made into a canopy is a snap.