FALL OF CONSTANTINOPOLIS
I've chosen Constantinople for my entry as well, with the wikipedia article
(and image) as main inspiration.
This is an extremely open map, with gameplay elements from Supermax (many paths of attack), and maps such as King's Court (extra bonuses for holding commanders).
Since all mosques attacks mosques and churches attack churches, there's a lot of options in regard of who or what to attack. You aren't limited by physical borders, but rather by what a given territory will add to your bonus or remove from your enemy. I've often known who or what to attack in order to keep a certain player from gaining the upper hand, but been unable to do so because of restrictions in movement or other players obstructing in the way.
With this set-up, nearly every bonus is under threat from several points, making it a slow developing map where it's hard to keep your bonus without protecting all your bonus territories (as opposed to defending a bottle-neck leading to those territories).
I believe this gameplay will yield interesting choices in terms of weighing whether to take bonuses for yourself and how to protect them, vs. the benefit of attacking an enemy and destroying his bonus. Both options will be available in many different forms every turn.
Regions (or bonus areas) are not separated by impassables, but rather by the machanics of the map, through the Region Commanders. You can go for a region with few churches / mosques and take the corresponding commander for a decent bonus, or you can go for a region with many of them, but will then have to contend with the difficulty of defending them.
I know this is controversial gameplay, or at least unusual, but I'm confident it will work quite nicely for 4-8 players. Less so for fewer players, but the large number of territories and free roaming should even out effects of a bad drop.
Ironically, my major concern is graphics; the size and proportions of the map. Some gates and perhaps a couple of the religious buildings might have to go, to fit it all nice and clearly.
Starting territories: All Mosques, Churches, Gates & Ships.
All neutrals start at 3, except commanders who start at 5.
I do humbly submit this entry for your consideration!