Ok... the background will have to go. It's giving me flashbacks. You'll have to think of something else, I don't think players will want to look at all those colours while they play... too distracting, and hurts the legibility of the map.
The background should be less noticeable than the territories and other important features. Right now your image is dominated by the background.
Another thing is thematic consistency. Widowmakers said it the best so I'm just going to quote him:
WM wrote:To best decide what style graphics to use, one must understand the purpose of the final piece.
Here are some questions that you can ask yourself before you make a map. They will help you focus you ideas and design.
Who are the characters in the map? (backstory .i.e. why is this map significant or a cool story)
What is your map about?
Where does it take place?
When does it take place?
Why are the events taking place? (again backstory)
How will the events unfold?
For example, let's say all the players are rock bands, and they have to conquer venues to get cash... you could have bars that give a small bonus, clubs that give a medium bonus, a few stadiums that give a high bonus... You could do a "rocknroll city" where all these places are. It could also feature hazards of the rocknroll lifestyle, like drugs, std:s, what have you.
Or let's say before you can conquer the bars and clubs and such, you'll have to put together your band. You need to conquer a drummer, a basist, a guitarist, etc... then you need a place to train, from there you could assault the bars... holding the record studio doubles all bonuses... and so on...
I'm just trying to say, there's much more you could do with the theme. Use your damn imagination man
