You asked, so here it comes! The paperback edition of the Books 1–3 Omnibus will be arriving on or before 1st March 2018, and it's a whopper!
The book is a large format 7x10" paperback, reducing the combined 1180 page count of the first three novels by almost half and coming in at 646 pages.
Like the Kindle version the omnibus paperback will come with a cost saving. The pricing is currently expected to be $30.99 in the USA, £22.99 in the UK, and €25.99 in Europe. This price point makes the print omnibus about 20% cheaper than buying individual paperback novels.
If you've already started collecting the novels in 5x8" paperback format, don't worry: they will of course continue. The second Omnibus, incorporating From Shattered Stars and Whom Gods Shall Fear, will also be released in 7x10" format. So whichever way you collect, your bookshelf will line up nicely!