A 32 oz/ft^2 loading model can be difficult to fly. Size matters. As noted, bigger is better when loadings get much above 24 oz/ft^2.
There is no upper limit on loading. Anything can be made to fly given sufficient power.
Whether it flies well, is a different matter.
Small and heavy is a twitchy difficult to fly situation...
For warbirds, larger... 60 inch span or > works well.