I think it is a bad idea. Sure, if you're the only passenger in F then no one is inconvenienced when your friend/colleague/potential-date comes forward to visit. But then that starts to create expectations: "They let him visit me on the last flight!"

The only compelling exception that I can see is a medical situation in which the F suite provides a doctor/nurse/attendant better space in which to assist a patient.

Even the "sit up front for landing to deplane together" strikes me as misguided. If there is a real need for priority disembarkation (to avoid a misconnection, for example) then far better than ground personnel are there to provide an escort after disembarkation.