I would like it to work as a room of human experts works with a moderator.
Alexa, how long will it take me to cycle to Netto?
Alexa sends this parsed query out to all apps it thinks can answer.
They respond with a confidence level and answer / follow up question.
Alexa decides which app to choose (the 'PageRank') based on a number of factors like has the query been seen before and how did each app perform for it, the app's answer success rate, has the user been given a response from this app before etc. etc.
The user should not have to install apps. Alexa should know all of the apps in the room and what they're good/bad at and select one to respond.
Surely discovery is the wrong way to think about this problem and Alexa needs to be elevated from a good speech parser.