I use PIK now and again if it's drastically cheaper than EDI/GLA. It used to be much much worse than it is now and when compared to other FR airports, at leats there is the luxury of shops, padded seats and even a carpet (comparing to Lubeck) in Departures.
It would be interesting to see if this airport is majorly upgraded and how major an upgrade it does recieve. The Terminal as it stands is pretty, the only thing that makes it different from when i flew from there in the late 80's is a coat of paint and a WH Smith!
I hope they re-open the Spectators Gallery, it offered great views of the airport and the surrounding area, and it even had a cafe and an indoor area for when the weather was bad (never foggy though
).
As for the main Glasgow Airport, I like the main Terminal, it is much better than the one at Edinburgh. The T2 section for LOCO flights is a bit of a let down, but it's only for check in and the main terminal more than makes up for it.