The first thing I was going to tell you after having read the thread was to lose the canister. Man, does it take up real estate!
If I could quibble at anything, it's the planting methods. Eleocharis and Hemianthus really do best when planted in much smaller clumps. Yep, a huge, tedious chore to do, but yielding much better results with regard to growth and spread. This is why I often scape with a glass of wine or a bottle of beer very nearby. Sorry to those who are underage.
Oh and another quibble, Iwagumis really only have a max of 2-3 plant species, especially in small layouts. You have too many.
I'd lose the stems. Leaves are too big. The anubia is even pushing it. The idea is to create scale and balance. The deception of a larger tank size.
Layout is a matter of personal taste. How many stones (petrified wood) do you have? I personally find that your Fukuishi & Soeishi stones are a bit too on top of your Oyaishi. I'd like to see more of a gap between the Fukuishi and the Oyaishi for you to get a true sense of Iwagumi. Perhaps it is indeed placed that way, but the plant species obscure it.
Sorry if I'm being critical. It's what I do. I will say that it's a nice little start and enjoy your little tank. I often find myself putting together little tanks with spare equipment. That being said, you should look into the Spec V, a much prettier tank, IMO, for this sort of thing. I have a planted Spec 2 and a Marine version, and it's just so much more aesthetic. Here's mine, but it's not an Iwagumi. Just a bunch of plants I threw together with leftover bits of wood.
Regarding stocking, I think embers, while lovely, are a bit too fat-bodied for a tank this size and will throw off scale. Pygmies are a great choice, but they are not bottom-dwellers, unless you are talking C. habrosus. There are three main pygmy corydoras species, C. habrosus, C. hastatus, and C. pygmeaus. C. pygmeaus & hastatus, are more mid-level dwellers and perchers, and don't always behave in the typical "bottom-dwelling" cory fashion. If you want a pygmy that'll behave like a typical cory, get C. habrosus. Another species to consider are boraras species. I've kept boraras and pygmies very successfully in a 2.5g planted tank. There is so much more to consider than inch per gallon when stocking a tank. There is a website that specializes in nano fish that has some excellent selection.
Ok, now I think I've had way too much coffee.
L