I'd suggest it is next to impossible to product a "good" magazine for the UK GA market.
For a start, I am certain (though I can't prove it) that a lot of the readership doesn't and never has flown anything. But they buy the mag so their interests need to be covered.
Next, the great majority of new PPLs stop flying within a year or two, so post-PPL readership is going to be relatively transient.
One could address a magazine at vintage aircraft owners (and admirers); that should work.
One could address a magazine at high-time pilot owners who fly distances, and fill it with stuff on IFR, advanced avionics, etc. This works in the USA but here the readership would be far too small.
So all the mags are hanging in there trying to do everything, and in the process please very few.
The things I really don't understand is the aircraft maintenance articles. Very very few readers will be doing their own maintenance anyway, and those that do ought to be able to read the manufacturer's maintenance manuals! Not some generalised tips in a magazine.
Personally, I get 10 minutes' reading for £3.50 - poor value.