Why not just use email
Because you end up comparing nine applicants across forty messages, and the one detail you need is in the thread you did not keep. Applications hold the same fields for every applicant, so comparing them is reading a list rather than an archaeology exercise.
Viewings
Book them, record who attended and what came of it. If you would rather not do them at all, accompanied viewings are a service you can hand over.
The waiting list
Most enquiries arrive for a property that is already gone. A waiting list turns that from a dead end into your first call next time something comes up, which is the cheapest tenant find there is.
Then referencing
When you have chosen someone, move them into referencing rather than making a judgement on the strength of a good first impression.