Subcities - Advance questions

I've read several older posts concerning where to build your sub-cities.  I understand the fundamental pros and cons of building them close vs. far from your main city - like mutual support/protection from your main city if the subs are close by vs. building the subs-cities in a resource rich area abet they might be farther away. 

My questions questions are:
1. What factors do you use to find the location? i.e. distance, near by resources, transport time, etc.
2. Of those factors in questions #1 you use to choose your sub-cities location, rank the priority from highest to lowest in importancy.
3. Do you use any advance tactics/strategy to support the sub-cities and what benefits do the subs-cities bring to your gameplay tactics and strategies?
4. Is 2 hours too far from your main?

I've read several older posts concerning where to build your sub-cities.  I understand the fundamental pros and cons of building them close vs. far from your main city - like mutual support/protection from your main city if the subs are close by vs. building the subs-cities in a resource rich area abet they might be farther away. 

My questions questions are:
1. What factors do you use to find the location? i.e. distance, near by resources, transport time, etc.
- the more far away the better
- maybe surronded place (by forts and oasis)
- good amount of forts
- not at the edges (harder to find your sub)
2. Of those factors in questions #1 you use to choose your sub-cities location, rank the priority from highest to lowest in importancy.
as i listed above
3. Do you use any advance tactics/strategy to support the sub-cities and what benefits do the subs-cities bring to your gameplay tactics and strategies?
- there are several strategies, but i dunno if theyre glitches till they got confirmed by support i held them back
4. Is 2 hours too far from your main?
- no, even 10 min could be too far if they wanna take ur city, so the more far away the better

Answering your question depends on your play style and level. If you are at a point in the game where you are still trying to make money to upgrade your techs then planting subs near high level inactives is important. If you are higher level then your priorities change and you may want to keep some cities near your main so you can load them up and jump them. The answer also depends if the bulk of your army is cats or cav.. There is no right answer. I think as you play along positioning your cities comes almost naturally because you will have a reason for having city X at a certain location. If you look at mine I can tell you a pretty good reason for why each one is where it is.