Good public transport links rely on a lot of inbound passengers visiting an area, and needing to get to a town or city. Most outbound passengers park their car, get a lift off their mate or take a shared taxi. It's cheaper, and much more convenient, than public transport.
I do travel to DSA by public transport if possible, but this is inconvenient for early departures or late arrivals. The passengers I have seen on public transport were a few odd Poles or Spaniards going to Sheffield. The specific 707 bus was withdrawn, just leaving the normal stopping X19 and 91 services.
So unless a load of foreign tourists start to visit MME I would not see improved public transport as viable or efficient.