Matt,
We do have a road map, right here:
guru.ijoomla.com/road-map/
We update it often with what has been completed.
The problem with giving exact estimates is that, learning from past experience, people hold it against us: "But you promised it will be done by x date, you are a liar!", yes, we had such reactions.
That's why we don't commit to any specific dates. You as a project manager must know that no matter how good the estimates are, there are always different obstacles that make the project go longer and these are unpredictable, in addition to that, during our extensive QA, we find bugs or logic issues that were not evident from the start and could not be predicted.
We are not trying to brush people off, we are just being realistic. Next week we will be releasing a new version with some great new quiz features. We thought it would take 2 weeks, but it took 2 months.
All we ask is that people have a little bit of faith in our process. We've been around for a long time, we are not here to rip anyone off or to play games with our customers. We always deliver what we say we would, even if a little later than people expect it.