I think the trip would be too long. There's a big difference between a 5-10 minute Skyliner trip and a 20-25 minute one -- that's roughly how long it would take to get from the TTC to EPCOT via Skyliner if it followed the existing monorail route, and that's assuming it could actually travel at the 11.5 mph max speed the entire way. That's actually impossible because it would require turn stations, so it could take 30+ minutes.
They could potentially cut it down to maybe a 15 minute trip if they could built it in a straight line directly from TTC to the EPCOT front entrance, but I don't think they'd want to do that for several reasons -- it would go through the middle of both the MK and EPCOT parking lots (meaning they'd lose some parking spaces, although it would be a small amount) and it would cut through undeveloped land that may not be suitable for installing support columns.