As the publisher of FSG and the custodian of its legacy, I have an interested insider's view.
I was nearly 40 when I published my first book. I was a slow starter - or rather, I was slow to gather my work together, though I had published translations, mainly of the Italian poet Montale, by then.
There are courses you can take to learn the mechanics of the business, like the Radcliffe course, but I don't think they teach you how to edit.
Poetry is not mainstream, but then neither is serious fiction, really. But I don't think there's a lot to worry about in this particular 'problem'. Why does art have to be mainstream to be significant?
Eugenio Montale - born in Genoa in 1896, died in Milan, 1981 - is one of the twentieth-century Europeans who has spoken most meaningfully to American and British poets.
The price of an e-book is a lot less than the price that we're charging for a hardcover book. It's about the same as we charge for a paperback. And that means a different revenue stream.