I feel as though a DCS map including the entirety of the UK and Ireland would be enjoyable enough to justify it's creation. With the upcoming DCS: Eurofighter it would be good to have a modern map featuring one of the Typhoons primary users. Also, due to the UK's proximity to Russia the map would be good for 'What if' scenarios to do with a future (or cold war era) air war. Also, if ED feels so inclined they could include other areas like the north of France, Belgium and the Netherlands. Or alternatively Sweden, Norway and Denmark.
This would be undeniably the most diverse and possibly even the largest map for DCS, providing mountainous regions in the Scottish highlands as well as urban areas like London, Birmingham and Edinburgh.
I hope that this idea some how makes it's way to ED as it is an idea that I (and hopefully others) would love to see.