After the rather anti-climatic civil war I had as Rome on Legendary it became obvious for me that the system is unrefined and possibly unfinished. Currently, the AI spawns more stacks than your standing armies, of similar quality (sans the experience chevrons) and all close together. That's great initially. But the fact that the AI doesn't use them for much but capturing one full province, means those armies it has will quickly starve out. By the time you gather up your loyal veteran armies, the loyalists will be reduced to a group of starving, undermanned armies.
The gamey, artificial and outdated Rome 1 type approach would be to make the loyalists emerging faction immune to attrition from food. This is however, a bad, immersion breaking way to solve things and it will leave many players with a bad taste in their mouth. You could get away with things like this when R1 came out (SPQR cities don't rebel, VH battles gave +7 attack/defence to AI units etc.) but not in 2013.
Also, we have the problem of the lack of a family tree, the lack of meaning to internal politics and the lack of immersion and caring for an army general. It is also quite useless to have a general with good governing traits since one can't afford to let an army to sit there so the guy leading it can govern a province (armies are capped as we know). So here is my solution:
1. Return the Loyalty stat from earlier titles.
If you remember in Medieval II, a general with low loyalty was prone to rebellion, taking his whole army with him. Characters of your house will be more loyal to you (bar some unfortunate random events like a young buck falling in love with your FLs wife and absconding with her). Characters of rival houses could be loyal to you... but if civil war hits they will heavily favour their own house (unless you have given them such a good position and title that it doesn't make sense to ally with their original house. And they have to be greedy and selfish for this).
2. Character traits should be displayed and should influence special events and civil war behavior.
Your FLs brother who has been loyal for 30 years, who won numerous victories on the field, who has character traits like "honest/prim" should not go to the enemy camp. Alternatively, a miserable wretched little cousin who has "ambitious/cunning/dishonest" will jump at the first opportunity to further his own position. Even to the point of leading troops to betray you when civil war comes/
3. Introduce the Provincial Governor mechanic.
It is historically accurate that Roman senators, consuls and generals would at some point, retire to become provincial governors. Especially if things in Rome heated up and they had to disappear form public life for a time. Caesar was governor of Gaul for 3 years IIRC. When assigning a character (statesman, general etc.) to the position of provincial governor we basically remove them from the character pool for several years, barring extraordinary situations like a massive threat to the capital/faction, or civil war.
Incompetent provincial governors can be the bane of a large empire. Boudicca's rebellion happened mainly because of a greedy and incompetent governor. Same with the uprisings in Syria and further to the east. Generally, when some major rebellion from Roman rule happened, one could find a really bad governor somewhere in the mix. Now, the player could recall bad governors or send an agent to... remedy the matter more directly. Recalling a governor before his term has ended can happen only when extraordinary evidence pops up that he is incompetent, like a rebellion, or a dignitary/spy discovering that they have been stealing from the taxes etc.
When civil war comes, the provincial governors will be weighed out and those not loyal enough would defect, along with their entire provinces, to the loyalist faction. Sure, it's a "realm divide" mechanic of sorts, but at least this way a really strong faction will pop up in your face and its troops will not starve to death 3 turns after they have appeared!
The governors also now don't collide with the number of armies allowed. When you see that a general would be more useful to you as a governor, you send him to govern, be it to raise income or suppress public order problems.
4. Make the game 2 turns per year at least and add seasons.
A quite simple solution that will double the general/governor lifespans to the point where we actually can see them gaining a lot of skills and a history behind their actions can be formed.
5. Add a family tree
Also a very frequently requested feature. The family tree can help you determine who is who and how to assign positions within your republic/empire/kingdom. Females should be born and should appear, and should be used for marriage and politics.
6. Add a popup message when a promotion is available to one of your faction members
Turns are hectic and long. One doesn't always remember to look if a promotion is available now. Also, promotions shouldn't cost so much gold, if they are won by virtue of many conquests, vanquishing a faction your faction hates, or by Heroic Victories.
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