We certainly have loads and loads of ideas for a sequel. Some new, some based on feedback, and a ton of things we did not get to implement the first time.
For what it's worth... One of the next games I am doing (Neopolis) is multiplayer only and similar to a degree to Eufloria type strategy. Ok, it's a cyberpunk setting, and it features garish "Crews" rather than seedlings, but I a prettty damn excited about it.
R