The Hackney link doesn't have a moving walkway though. Part of the problem around OOC is the large area of industrial land alongside Hythe Road (Cargiant etc), not currently being redeveloped. In addition to any connectional function, a Mitre bridge or Hythe Road station would be serving low density employment only, and a new south entrance at Willesden Junction could serve much of the same area in the event of redevelopment.
I agree this a large chunk of connectivity missing. With the new bus hub at OOC There'll probably be routes serving some of the potential destinations.
I'm all for moving walkways and APM shuttles where there's sufficient demand, between major termini such as St Pancras and Euston. I don't think there will be at Mitre Bridge/Hythe Road.
I think the answer to West London Line connectivity is to reroute at least some WLL services via Willesden Junction low level to terminate at Old Oak Common Lane. Additionally, a new low-level platform for these might be provided on the south side of the fasts at Willesden Jn, with a footbridge linking across the WCML tracks to the high level platforms. There's also potential to link the industrial area to the south to Willesden Junction station with a new entrance if that eventually gets redeveloped. The Southern service might also serve the low-level platform. Maybe the Southern paths could be subsumed into the LO service and also diverted to OOC Lane. A total of 8tph LO on the WLL might alternate to terminate at OOC or Stratford so (say) 4tph Clapham Junction to Stratford and 4tph OOC to Croydon. As to a new station on the WLL itself, I think a more useful site is a little further south, convenient for Hammersmith Hospital (and the prison next door!).