Yeah, you gotta love jojo's scapes. But I do see your point. There's so many ideas that get thrown around a lot because 'they work', and very few people have a distinct style. If you notice some of the scapes at aquascapes tend to use really oversized hardscape materials which turns out to be really refreshing, but I think it's hard to pull off unless you have a shop full of branches and rocks, lol.
I like the idea of the erios. I personally think the textures would really pop if you planted them amongst the river stones. That'd look very neat. I've worked with m. umbrosum before, and I have to tell you, it's definitely not for everyone/every tank. It grew so fast in my 55g that I'd have to trim it 2x a week just to keep it from unrooting, but I'm sure that will vary. It might be just me, but I think that echidnodorus sp. vesuvius would look really neat with the wood and dark sand. Green doesn't get much brighter than that plant.
Anyway, keep the updates coming. It looks very promising.