You could always use your Under 160 captain to captain the Under 140. Worcestershire's Under 140 captain doesn't actually play for the Under 140 team... I could understand if the player had a lack of willingness to do it though.
I guess the likes of Warks/Worcs/Staffs would avoid the 4NCL, Warwickshire Open, possible Staffordshire Congress, Birmingham Rapidplay, and that's about it. They don't allow for Dudley for some reason. The Lancashire area seems to have a thriving local congress scene that Greater Birmingham area is devoid of (did I really just say "Greater Birmingham"?
). I guess in some respects, it's a good problem to have.
I don't think the fact that often players dip below 175 or even 150 is much of a problem. Warwickshire went down to 151 for the GMan match, but they were devoid of an a lot of 2100s who would normally compose their 4NCL team. Thomas, James, Baruch, Mason, McCumiskey to name but a few. Staffordshire's board 16 was 164. In the minor Open, Shropshire went down to 138, Derbyshire to 127 and 115, Worcestershire to 88 and 130, Leicestershire to 153 and 154, Lincolnshire 143 and 145. So there is a lot of overlap with other sections. County 2nd teams start where appropriate. If Greater Manchester could avoid clashes, I'm pretty sure you could be a match for Staffordshire and Warwickshire; you always used to be.