I don't want to hijack the thread or divert the topic away from Pentax. But the following data may be interesting towards the question how important FF is within the DSLR world now. As this data cannot (yet) come from Pentax, I think the following may apply to this thread.
Reikan FoCal, a computerized tool to fine tune AF calibration for Nikon and other vendors, has published the usage proportions by camera for its tool.
It is a safe assumption that only enthusiast and pro photographers (like wedding etc.) care enough for AF fine tuning to purchase and use said tool. Therefore IMHO, the usage proportion is a good measure for FF adoption among enthusiast and pro photographers in the Nikon world.
This is the graph:
The top two bands (orange and gray) and bottom two bands (light blue and orange again) are APSC (D300/D300S/D7000/D7100) and together amount for roughly 20%, about 80% being FF.
With the D800 being over-represented because of its notorious left AF point issue, one may still say that maybe 2/3 of enthusiast and pro photographers in the Nikon world use FF, partly or exclusively. E.g., there already seem to be twice as many D810 than D7100 users.
One may of course argue that FF users shell out more money to buy said tool. But the same holds true for lenses and accessories, meaning the direct and indirect business revenue charts by camera model within Nikon corporation will likely look the same as above graph!
This leaves the entry level market (D3xxx and D5xxx series which runs between $500 and $750) as the only one left for APSC, with little or no indirect sales triggered by it. And this segment already sees stiff competition from mirrorless and enthusiast compacts.
I think this leaves no options for what Pentax has to do next ...