Honestly, in my opinion I don't think the problem lies with auto-blocking, it lies with the raised block not lasting long enough. Even with self-preservation, using a scutum, I have to hit block every 15seconds. That's a little too often, I think. I would like to see an increase in the wield rates of all shields. Perhaps something along the lines of 30sec for a scutum and it increasing all the way up to say 45sec to 1min for the smaller shields, self-preservation obviously augmenting those numbers as needed.

The benefit of this is for smaller, faster fights we would essentially still have a kind of "auto-block" as we wouldn't be hitting it every 15/20sec and would be able to focus on other abilities. However during large-scale NMs, instances and other 'boss fights' we'd still have to be vigilant about watching and maintaining our block without having it become a nuisance.

Also, as stated above, the inclusion of a "Shield raised" icon should be mandatory.