Thank you guyz for your comments...
this was not meant as "1 man job".
I have small firm behind me that is willing to invest in this becouse they liked mine idea.
I guess that using Unity would be better but also is more staff and resources demanding and since the investor is happy with 2d engine if it can handle standard 8player multiplayer with no fuss.
Thats why i ask if C2 is capable of this...