We have a number of smaller tractors built like the one on this page of our website (note the one shown is split in two and is a very early attempt at this, most we've built since then are just singles and hence twice as wide):
We put eyebolts on each end and thread a rope through them and then can lift them that way. That allows us to move them with just one person if we want, in a sort of jury-rigged way, a bit at at a time. But I like your design a lot, may have to try it the next time we're building them!
However, are they light, or heavy? In the spring and fall we get wicked winds, and the nice thing about the flat tractors is they don't get blown over like the hoop houses, which if we don't tie them to trees or stake them down seriously, blow right into the east pasture.
I like that! Is that the nest box in the back, with a panel so you can get the eggs out without having to climb in the whole thing? Very clever. And it looks heavier too, which would be important here, with the winds we get spring and fall.