Could be good to populate the Metro server and turn it around my nemesis map I hate and never been able to play but have played and helped but is super hard to keep half full or get started and keep going it is off and on just my 2cents from watching the last cpl weeks. Seems the other 3 may have dropoffs but they always recover.
I dont think it would could idea to mix it with metro. metro caters to a certain group. Soon as the map switches people will leave.
I'm not sure, the only reason I play metro is because its not vanilla and I've gotten tired of the originals. So, just saying its not just catering to one group. Personally I'd like a mix, but I know where you are coming from, Wize.