Wondering what difficulty people choose usually...

[Titus Marcellus Scato]

I play H/M. I have never tried VH campaign difficulty as I have enough trouble completing (or rather failing to complete) campaigns so I stick to H campaign difficulty. I recently tried the medium campaign difficulty and found it to be rather dull.

Me too. H/M seems the best balance, provided you make the battles you fight personally more interesting by allowing the enemy to either outnumber you on the battlefield, or to have more higher quality units than you. Let the AI have either the biggest army, or the best army - and you'll enjoy the battles.