We discussed fractal cosmologies here: What would a fractal universe tell us about Time? I'd say there is a serious risk of saying something like 'these are two complicated things so they are the same' - an approach generally based on baffling the uninitiated with jargon, rather than making true headway (widely found in pseudoscience claims about how quantum behaviour is weird & consciousness is weird so they must be the same thing). We can link minds to complexity theory and emergence, sure. But we just don't find infinite-levelled self-similar structures like in Mandelbrot's maths, in our world - the Planck scale & size of the universe provide defined limits.
I'd say there is a fundamental parallel between what Plato is doing with his Forms, with the monism of Shankaracharya in Hindu thought, and with Leibniz's monads. That is, creating a framework which can relate cultural & religious diversity, into a single structure. While not consciously motivated by political aims, I'd suggest this methodology fits a kind of 'spiritual entrepreneurialism', where it gained attention & support for providing a basis for cultural unity, without requiring homogenisation.
Leibniz aimed to bridge the math-cult Plato took from Pythagoras, with his religious ideas, unifying mathematics & spirituality. On the mathematical monism part of that, I'd say Lisi's proposals about E8, are a better candidate for manifesting something compatible with Leibniz's ideas, than fractals.