There are many, many problems with the GA "scene" at the moment but they all stem from from two things, Cost and over-regulation.
The cost of flying in this country is ludicrous, which stops the inward investment needed to provide things like new a/c or avionics.
The over-regulation for things like the IR, completely removes an entire strata of PPL's from flying G-reg machines. It not only is a financial issue, but also a safety one. If the IR was more useable, then more people would train for it and have more currency and capability.
At the moment, PFA and farm strip flying is expanding because they are seemingly more relaxed and sensibly managed. We all need to keep aviation as free and open as possible, otherwise it will end up being a sport only for the rich or the totally obsessed, rather than being for all. I am constantly finding new ways in which we are being scr*wed or bullied and since we are such a disparate bunch we can't make strong enough representation for ourselves.
Clubs can make a difference, but there are still too many sharks and incompetants in this business. I only know of one club run on sound financial foundations and I'm involved with it, all others I've known have either been "dodgy" or simply hopeless. This again stops investment as there is such a bad record industry wide, even though there are many good and sensible people involved in GA flying. The bad spoil it for the rest of us.