Consider open sourcing your firmware / software so that the open source development community can contribute.
I applaud you on the fact that you have a telnet API that can be interacted with. This was specifically one of the reasons I chose Heatmiser Neo. I have written a number of extensions on the back of that which would be great to incorporate directly into the hub.
I appreciate that this would be a big step, but doing something like this could massively improve your market share as more people contribute to making your product better.