Just curious what colour was the house before your painted? Was it barn red?
How close is the shed to the house? Can it be seen from the road? Can you see all sides of the shed?
Who would be doing the painting? If you are the one who will be wielding the paintbrush and buying the paint then go for it. If you have to pay someone else to paint are you will to pay out of your personal budget? As others have said you will need a lot of paint to cover the red. First a very thick undercoat, perhaps two coats of it, then at least 2 coats of yellow. Lastly the trim will nee to be painted out. I would guess about 6 days of work, just for the painting, another 2-3 for the prep.
From where I am sitting I can see into three neighbours back yards. One has a clear stained cedar shed, the house is creamy yellow. Another has a white shed that matches their house, the third has a blue shed and white house. All look good.