I'm in favor of making the tyrant appear more threatening by means of sound and graphics effects. However, be aware that this won't prevent tyrant camping, as it doesn't matter whether you know that one is around or not (it will still slash you badly once you enter the base and without knowing its exact position your chances to first-strike it don't increase).
The Tyrant being used as it is has other roots. In Tremulous 1.1 it was a strong base attacker since health points were more important than mobility, which changed drastically as the turrets were modfied (atleast that's the impression of someone hwo barely played 1.1, so correct me if I'm wrong). In GPP the Tyrant gained a trample attack that was very strong and turned it into a killing machine, but it was still relatively weak against bases. The trample damage was lowered (just like the goon pounce damage) to put a greater focus on regular slash attacks. Defense has always been a strength of the Tyrant but by now it's its only strength, which is why you only see them camping. However, making it a stronger attacker is a more viable solution than making it a worse defender (which would equal removing it from the game). The Tyrant is not yet on top of my TODO list but at some point I will certainly rework its role.