[Question: Holding Strategies] Is it better to consolidate your holdings as a duke, king, or emperor in few counties, or is it better to spread them out across counties within your controlled duchies?

I know what the obvious answer is that most people are going to champion: consolidate them so you can group your raised personal levies quicker!, but here are some of my thoughts on the subject:

When consolidating holdings into two or three counties, stewards sent to collect taxes will be more effective, as they'll raise the taxes in more holdings per-county than if the holdings were spread out. Obviously it's also easier to consolidate your personal levies when raised as well. Additionally, increases in Castle Infrastructure and Farming will likely apply to more holdings, assuming you've built the majority of them in your capital county; this is made even more effective by building a monastic school and a college.

When considering spreading out your holdings across your (presumably two) duchies, nearly ever advantage you gain in consolidating becomes a disadvantage. The major benefit of spreading out your holdings, I've found, is that you have more cities and bishoprics as direct vassals. I regularly raise city and church taxes to harsh and large respectively, and find it fairly easy to manage the opinions of these vassals. Conversely, if you spread out your holdings, your counts will presumably want control over these cities and bishoprics, giving you a fraction of their incomes (I think) - and it's worth mentioning that Feudal Taxation is a much more dangerous thing.

I'm a relatively new player to Crusader Kings 2, so my first question is really this: have I missed anything in my considerations? Is there anything about the mechanics of these systems that I am misunderstanding? And the major question, obviously, which holding strategy do you favor and why?