I think you do get two types of players depending on the maps...if you regularly have Metro and Locker, you will get a lot more of the nade/tube/etc. players who just camp and pad stats. A lot of good players don't tend to like those maps as much, just my opinion. I don't think you have both in a rotation if you are only picking top 5 unless you want a lot of those same players in the server or the people who will leave right after those maps are over. Just IMO. We want REGULARS who will stay on our server.
Anyways, my top 5.
1. Zavod
2. Propaganda
3. Caspian
4. Paracel Storm
5. Metro/Locker (you have to have one of these in to keep some people happy)
I like the idea of different modes or playing scrims, tourneys, etc. to mix it up. The US/EURO matchup we did months ago was fun going back and forth on maps and servers, etc. Maybe that type of thing in the public area, setting it up with registration ahead of time? Just a thought.