Hi Nathan
We have a garden hose cart, and due to our tiny yard it needed to hold at least 350' of hose, and the kind we both like was 5/8". This put us with a lot of weight, and the "giant" sized cart we got held, and reeled the hose just fine, but the wheels were for chit. I replaced them 4 times before I put on the ones I listed. Even though they were HF, they absolutely kicked all the Amazoo, and other we tried to the curb, and now they have been on the cart, getting pulled all over the place, loaded to the gills, and without issue for 6 years now. Longest we got out of the brand X variety was 6 weeks type of deal.
So around 30 bux a wheel sounds like a lot, you will only cry once. They are much better wheels, just holding them in your hands, loaded they are the ones to get. I don't think this cart will have that kind of weight, but for 60 bux, you are guaranteed they will last forever. Also they are run flats, so every time you do move it, they will roll, and you won't have to fill them like most of the Pneumatic junk in the lower price ranges. I used to use that green slime, now I use run flats, the slime is great for one season, starts to get expensive year after year. Dragging an air hose to the XYZ, and filling it only really takes a minnit, but it just is not one of things in life that make me smile, more PIA frown.
Your reasoning for using the smaller can for throw out is a good one. I always think of my shop. 12' ceilings was a smart idea, me thinks. Always enough headroom for single person sized equipment. I knew you had a footprint limitation, didn't think to look up.