Why do you keep posting requests everywhere? You make one in the WIP thread, you've literally just made a request for C400 repaints, now you're requesting a massive WM map? And who is this "you" you are aiming at? The entire Fellowsfilm community? The UKDT?
There are some who take repaint requests here - have you considered giving your requested repaints a go yourself, though? - but I have not seen one member on this site, and other relevant UK OMSI sites, take requests of a map of such scale. If you want a high-quality, high-scale West Midlands map, expect a long, long wait and the definite involvement of a development team, and the strings attached from all that. I couldn't even wrap my head twice around the OMSI editor, so I can't really help there.
I think its a shame we don't have many high-quality inner city maps - and maps recreating real-life routes - for UK OMSI, compared to the European scene, but going around requesting all this on Fellowsfilm, and more, I do highly doubt this will really get you anywhere for your requests. To be frank, I think it's a little bit frowned upon here.
What exact size of the West midlands are you on about? Birmingham & Surrounding areas? Extending out to Coventry, Wawrick, Lemmington Spa? Wolverhampton? Whilst it would be an incredible map, this ain't gonna happen unless a new game comes out, Omsi would never run a map so big.