I tried some scanning on a Plustek 8300, which is supposed to be the fastest. The process is still extremely manual/slow and I don't think it's practical on a large scale. Many families who owned cameras in the 60s-70s-80s-90s will have potentially thousands of negatives to scan, but I don't see a solution that will automate that digitalization process.
Software could also use some improvement. Automating batch correction and clean up should be easier, IMO.
This really isn’t my area but it sounds like nothing is fast. DSLR may be fastest without just flat out hiring someone else to do it. But even with thousands of shots that would still take quite a lot of time.
And yeah, workflow is the thing that seems the worst. That seems like a great place to try to improve things to get a sale.
Software could also use some improvement. Automating batch correction and clean up should be easier, IMO.