Dear Sir,
We did many similar projects to your game, some of them very complex.
We are international game development company with HQ in London and we did over 160 games.
We have experts in all fields of game development, multiplayer, user interface, 2D, 3D modelers, graphic designers, server and backend and mobile options, iap, leaderboards, level designers.
We need to check with you about full details of the project to give detail proposal.
Thanks,
Miodrag