I think getting a mic is a good idea, you won't regret it.
I played GTAIV a lot and I'd have fun helping people out. In the beginning I'd give people high speed motorcycle runs to whatever vehicle they were looking for.
If you had a mic it was easy for me to just use mine and ask if anyone needed any help. If you didn't I might occasionally message someone but that took a a hell of a lot of time. Not that you'd necessarily need anyone's help but it adds that extra dimension to me