The problem with offering a sort of "premium" option - in addition to cheaper options - is that it's very, very hard to anticipate how many people will choose it, given the cheaper alternatives. For full-color, hard-bound books, you still have to do it the old-fashioned way, ordering months in advance from a printer on the other side of the world, and it costs a bundle. Five digits.
Print-on-Demand is simply not capable of doing those sorts of books in any quantity, at a cost even remotely close to being feasible. Remember that 80% of the sales of color books is through retailers and wholesalers, who want substantial discounts. You have to sell a lot, just to break even. And that's exponentially harder if there are simultaneously cheaper options for the same product. (Not to mention that retailers will be very reluctant to order the expensive books if they know that customers can buy a cheaper version elsewhere.)
So it would be very easy to get that wrong. Especially for a topic like 18th century, which is not one of the traditional "big three" (Ancients, Napoleonic, WW2). And I can't afford to get anything wrong.
In other words, if I offer a premium hard-bound color book, then I can't really offer anything else, except maybe a very cheaped-down B&W PDF.
I suppose it might also be possible to do a "Magic 500" or something like that, in which - if I can get 500 pre-orders - I can go ahead and do the full-color book. I've never taken people's money that far in advance, though, prior to even printing something, and it makes me nervous.
Or, If people are willing to do without a full-color hardback book, then that opens a lot more options, because it makes Print-on-Demand cost effective.
Finally, it should go without saying that I'm a one-man "company" who also works a full-time job doing something else. Customers obviously want me to produce every game in seventeen different variations, but producing each one takes months of work and often considerable expense. So if you want the game sooner than later, you'll have to accept that it won't be done in every imaginable format simultaneously.
Nothing has been decided yet. But I'm leaning toward doing a traditional soft back book with color cover and B&W guts, and then offering PDFs in both B&W and color.
Then the cards will come in both a free basic "starter kit," and the full color, full set.