It would certainly help alleviate some of the inner-city congestion that Plymouth seems regularly plagued by but I'd be surprised if it ever happened. Is that location the same as where the original Plympton station used to be?
Plymstock too would benefit from such an initiative, by re-using the old Turnchapel/Yealmpton route however the bridge over the Plym is currently being converted into a cycle route and I think there's been too much development along the course of the trackbed anyway.
The old Plympton station was positioned further towards Hemerdon. In fact it was at the foot of Hemerdon Bank, like Bromsgrove station. That is being moved in part due to its placing on the Lickey Bank and whilst Hemerdon is not as severe a better site would have advantages. Parking would be a problem here as well. I am all for reopening and generating higher usage from Plymouth's suburban stations. Exeter can do it because there are more regular services, in part at least.
Maybe if the Okehampton route is reopened in some form then a Plymouth Metro could work in combination of an extended Devon Metro.
Any site along Plymouth Road could be used and I think there are other derelict places. Notably nearer to the Centre of Plympton is the old Co-op Homemaker store. This could solve the problem as well as there being extra space to potentially avoid standing on the 'Main Line'
But I too expect that this will not happen. Plymouth Council often does NOT seem to have the vision to push these schemes
