The problem with the “latex rendering error” in my last post can be partially solved by adding even more brackets to the variable name (symbol). Of course, this does not help with things like factorial.
@variables var"{x^{+}_{A,\alpha_{1}}}"
Note that in the output, the second-order-subscript “1” is not represented properly because Latexify escapes the underscore. I don’t think there is a way to mitigate this right now, short of editing Latexify.jl sources.