Per John:
If you've got an Access UI that works, I can't think of any reason to migrate to
another platform unless performance goes down the tubes when the DB is migrated
and somehow the other platform can remedy that. OTOH, keeping the same UI and
feeding with with stored procedures would probably accomplish anything that
another tool could.
Even switching to stored procedures is a huge job that means re-engineering
all the editable bound forms, and it's usually not necessary.
Converting queries to views and/or stored procedured is a good idea when...
1. A particular Access query can't be convinced to optimize well using linked
tables.
2. There will be multiple front-ends and you want to move much of the business
logic to the server, so it can be managed in one place without changing
multiple applications. Note that if you have SQL Server 2000 or newer, you
can often do this with Views and Instead Of triggers rather than stored
procedures, which is a much more Access-friendly way of doing it.