Getting serious for a moment, perhaps 'The Guvnor' should go back to his roots and define/decide what he wants his Forum to be. It's pretty obvious where most of the members have come from, and why. My assessment is as follows, I'm sure that I'll be suitably corrected or admonished for wrong assumptions:
1. A 'Workbench' thread for Cynric to display and share his modelling - layouts, locos, stock, thoughts, workshop techniques;
2. In a setting where it would not get lost and buried in amongst heaps of chaff and irrelevancies;
3. Where those of like mind and similar persuasion, especially those already known to each other, could 'club it' and be invited to add their threads.
An alternative might have been a S7G Forum, but such does not (as yet at least) exist. The FRMW certainly does not fit the bill, due to editorial control amongst other reasons.
Clearly there is a natural GW bias, and there really is no harm in that, especially given a willingness to embrace others with a similar mindset but different railway company allegiance. Let's face it, the modelling techniques are pretty much the same, only the subjects differ.
The problem with an ill-defined strapline is that any 'Bachby type' with a trainset comprising a Hall and 2 Hawksworth coaches could be enticed to join. I've seen the split on the LNER site where there are clearly different groups of member, and where the toy train types don't give a Tinker's cuss about accuracy or fidelity. Conversely, the mention of larger scales might tempt those running LGB or Skytrex round the back yard. That said, there's absolutely nothing wrong with outdoor modelling and the extra challenges that have to be overcome, same as there's no problem over the period someone chooses to model.
So Cynric, who do you want to see on your Forum? Any GW modeller? Only 'proper' modellers, especially those modelling the GWR, but in any scale? Or in any scale for GW but 7mm (or S scale?) and above for the rest of us? Finescale only? It's your Forum - you define the parameters and the marketing types will charge you a fortune for the strapline...