Regarding (1), at this point I believe that String theory is still incomplete. It can make some broad predictions (parts of which might be more or less testable

Regarding (1), at this point I believe that String theory is still incomplete. It can make some broad predictions (parts of which might be more or less testable, but most will be in the Planck-energy scale), but so far it's proven difficult to fill in all the gaps and get something equivalent to the Standard Model. Basically you've got a few too many degrees of freedom and most of the predicted behaviour is well beyond the energy scale that we can reach experimentally.