Startup time for the sim takes usually a couple of minutes for me. In the meantime i mostly replying topics on this forum 
When pressing the fly button, i should be on the runway in max 5 minutes, if not its alt-F4 for me and i will try it again. So far this only (frequently) happening with the FBWa320. rest of the planes (addon, like dc6 or default) are ready within 2- max 3 minutes.