Let's see what ranking allows:

1. People to exist with just a subset of their skills, amongst those with a subset of their skills. This gives rise to far more tactical scenarios than if we were all heroes.

2. Exp penalties. Would mean nothing if we were all heroes.

3. Learning the lands. People wouldn't bother visiting most places if not to rank.

4. Setting up ambushes etc. Ranking increases incidences of resting, being engaged in combat and thus vulnerable, learning skills, travelling more predicatably etc.

5. Ranking forces people into alliances/risks that they otherwise wouldn't make, because of the risk.

This applies to lowbie ranking as well as non-lowbie ranking.

Therefore, despite the annoyances like getting stuck at level 35 as an ap, 34 as an assassin (not that this ever happens), 39 as a warrior etc, I am a huge fan of ranking, despite the tedium of it.