As I mentioned previously, if you want a Pentax APS-C mirrorless the K-01 is it!
Can you explain why you feel an adapter is needed for full control of FA, DAF and DA lenses as they're native lenses for Pentax. Are your thoughts about using them on your Olympus? If its that, Pentax isn't likely to produce it!
You don't of course need to jump to a 645d or even a 645z unless you want to; don't forget the K-1

I always wear a crash helmet to prevent this!

The FA* 24/2 AL [IF] isn't bad at all. Prefer it to the Sigma which I also have.
Looking for a FA 20mm f2.8, I adored the old K f4 version which got stolen, I have an M version which lacks something by comparison.
K 17/4 Fish-Eye (OK not AF but pretty well could be fixed focus!)
Intend to get a K 15 & K 18 when I see them for the right price/condition, mainly as collectors items rather than to use though. AF doesn't matter with 20mm or less as one can have from several inches to infinity in focus with a small aperture and what's wrong with twisting a focus dial anyhow!?
If Pentax brought out a new wide angle it would have to be competitively priced before I considered purchasing it. I'm pretty happy with the old lenses given chromatic aberration only really rears its head when pixel peeping. It is when using the older lenses on APS-C it gets magnified and might be a problem. I find CA with the older glass used at its intended 36x24 isn't normally a problem other than with some of the cheapie F and FA consumer zooms which weren't sold as top rate glass; and some of those can be bad veering on unusable!
Also have the Samyang 14mm and 12mm Fish-Eye. Not AF but at that focal length AF is unimportant and both are fine and fit for purpose probably at less than a third the cost of what a new Pentax equivalent would be.
So not unduly worried whether Pentax bring out a new FF wide angle or not, I've more than enough to be getting on with!

I have a K-1 and several Pentax FF Wide-Angle auto-focus primes already.
(Can't find that option to tick in the poll!)

You won't be much help writing people's essays for them with just a lens. I was under the impression that submitting an essay as your own work for an exam when someone else wrote it is illegal. I presume this is why more importance is going to be given to end of term exams now with less reliance on (someone else's) course work. I guess in reality you've just a come here to spam given it has nothing to do with the thread you've posted your backlink in.

Beware of clicking links in spam posts, especially when they're promoting (anti) virus software.

As mentioned by the OP, Sony do a FF mirrorless for which there is a Pentax lens adapter available. If mirrorless it has to be then that is a viable route. Quite a few were using Sony Alphas with FF Pentax limited lenses before the K-1 came about; I wonder how many have now given up the Sony to use those lenses on the real thing!
Having tried bridge cameras with electronic viewfinders that isn't the type of thing I'd particularly want to go back to using as what you're looking at happened moments earlier whereas an optical viewfinder gives a real live view! IMHO electronic 'live view' has to be a misnomer. As I suggested earlier, a hybrid option would be fine.

Trouble was, it didn't prove very popular so further development, perhaps to what you would like, was discontinued. A hybrid viewfinder would be nice then have both worlds available.

Look out for a K-01, that's the nearest.

To me the big danger of fill in flash is making the subjects look like cardboard cut-outs. Some of the examples presented 'at the other place' are seriously affected by this appearance. This is because the shadows indicate the light is coming from a certain direction but the visual appearance of the subject contradicts that.