Speaking of large, aggressive animals, J=A=L is circling this thread like a hungry shark who smells blood.
Nonetheless, the topic is a meritous one (although probably should be merged with the other trolls one and delete the restrictive poll) so I'll weigh in.
Recommendations:
1. Unlock morale on all troll types
2. Enable run_amok so there is a chance when troll morale breaks
3. Troll formations to be mob only
4. Keep Olog HP at 6, reduce mountain trolls, cave trolls and catapult trolls HP to 4.
5. Lower troll mass to ~40 (currently 80-100). Men are ~1, mumakil are 80.
6. Reduce armor by 4 for all trolls, increase defense skill by 4 points. This will make arrows (and rear attacks) more effective without taking away from their overall melee defense.
Just my $0.02