Years ago I put a 48" JD, a 21" Toro, trimmer, blower and gas cans in a Ranger. Worked out of it for the first two seasons. Easy to park and maneuver. Pain to load and unload dang near everything at each job. That said, it was what I had. Way easier to load and unload from a trailer with a ramp gate.
If you can swing a trailer, your s-10 will pull a 5x10 nicely. Good size for a solo, or even with a helper. More than enough for your current mowers, and room for that 52"-54". A single 3500# axle is the way to go. A 2000# axle is pushing it when you add your next mower, or haul any dirt, rock, sod etc.