Hey!
I created some map with this generator and the maps looks awful. Or just that map I've created for our server.

http://i.imagebanana.com/img/21l46y7q/Bildschirmfoto20130421um12.56.39.png

Please give me an answer about this topic :(
I want to give them players a good feeling on this server, without any breaks in biomes.

It seems that parts of your world are generated by minecraft 1.4/1.5 generator.
There are biomes that aren't generated by 173generator(Extreme hills, swamplands).
Which plugin and bukkit version are you using? Do you see any errors on startup?