I'd like to see multiplayer too. I guess everyone knows its a lot of work and for a rather new game its a big gamble. Having a game without content, yet a multiplayer doesn't sell. But a game with a lot of content and no multiplayer looses its long term motivation rather fast. What I mean is please don't say never to online multiplayer.
In my opinion investing time to develop a local coop has next to none impact on the gaming market. Look at Factorio, if that game supports only single player or local coop, I bet it would cut the player base down to 1/10th.
Also using TCP for the multiplayer connection and a snapshot system for transferring world states and updates, should be enough to support Nimbatus, as it is in 2d and the movements are easily interpolatable. I know there is a lot more to this, but I see many games and developers starting with UDP and their own network protocol (Factorio had peer to peer connections ) that they burn time and money.
I hope I don't sound arrogant. Have a nice day and greetings from Germany.
