The facilities at BHX are now second to none but I agree the airport is under utilised.
I think BHX will come good in the future with the runway extension now going ahead and its close proximity to London.
The South East is congested, the Government wont consider a 3rd runway at LHR.
BHX is the natural alternative.
I can see BHX 'taking off' in the next 5-10 years.