Please show me how to print a lower case 6.

Raise it a little.

Are there line-of-sight issues

Yes, the satellites are low in the horizon. I'm in southern Norway, and most of the time I'm unable to take advantage of EGNOS (WAAS) unless I have clear view to the North Sea. However, there is an internet service calles SISNeT, which delives EGNOS signals to ground users. Likely to be a bit expensive...

You simply cannot stack lenses like that.

Well yes, you can: It's called afocal photography.

It seems to improve autofocus

Well, maybe improve accuracy in some cases, but the contrast detection AF of non-DSLRs is usually slower than phase detection AF of DSLRs. The very best CDAF is comparable with PDAF of average DSLRs, and then there are the sports cameras...

Have you tried a modern digital viewfinder? For example the VF of the Olympus EP2. I'd say it has enough resolution to not make a significant difference. It has 100% coverage (of course :-) and 1.15x mag. And for those still life photos you can magnify a portion of the view (up to 10x?) to fine-tune the focus. And best of all, the flange focal distance is small enough to use Leica M-lenses at infinity -- but the 2x "crop factor" may be a curse or a blessing...

Many large manufacturers of DSLR's, such as Canon and Sony, have started removing the mirrors from their prosumer-level camera's in exchange for sensors that can work in different modes.

Well, Canon (and Nikon) are still on the fence. Nikon may (or may not) present a mirrorless system camera at Photokina, Sony has their new NEX-system, then there's Olympus and Panasonic (micro four thirds), and yet another system, Samsung NX. Even Ricoh is jumping on the bandwagon, in their own idiosyncratic way.

Just don't talk to the people who want super wide angle lenses (easier to do with a larger sensor)

Olympus has a well-regarded 7-14mm rectilinear lens. The widest non-fisheye for APS-size sensors (Canon, Nikon...) starts at 10mm, which gives a bit narrower view than the Olympus lens. The widest rectilinear lenses for 35mm film/sensor start at 12mm, a bit wider than the Olympus lens, but there are only two choices, the Sigma 12-24mm (terrible corner sharpness and the usual Sigma quality control), and the 12mm Voigtländer Heliar, which is only available for rangefinders. I think Olympus has their bases well covered (that is, apart from the lack of primes and fast lenses).

What limits wideangle lenses is not sensor size (how many ultrawides do you see for medium format?), but the mirror box. The closer you can place the lens to the sensor, the more symmetrical (and smaller and well-corrected) you can make the lens (compare Biogons and Distagons). Making an excellent retrofocal ultrawide lens is a damn hard job.

(I'm not an Olympus apologist, I use the right tool for the right job.)