I'm in a similar boat to you, having played RTW on and off for five years. I still like to play as the Romans as I like their legions, but I need some kind of role play / storyline to keep me happy.
To do that I need the characters to hang around a bit longer, so I have changed it to 12 turns per year. This makes my family members very important to me as new ones will not be around for a while and I never adopt. I have begun sending out one army with a FM as general and 3 armies supporting him with Generals recruited from Rome. If the AI attacks my FM I am happy to have the AI generals join the battles as I don't care if they die. Consequently I have had quite a few 4 on 4 battles with a bit over 20,000 troops on the field. These have felt quite epic even though I have had to turn down all the graphics during those battles. When a FM dies it actually feels like a loss as he has done quite a lot for me, and the promotion of a new FM to command an army is a decision done with some thought. I always hated the fact that after a short while the Family Tree was far too big to read without scrolling, with too many FM's I gave little to no thought to who they were, what they did or how I replaced them.
I also don't really conquer regions during the first war with a faction. I never (rarely) start wars, but if they want one I will send one seige army and one field army around the back to lay waste to their cities, slaughter their people, plunder their treasury and demolish all buildings. If they come back for a second war, they get conquered.
I like a nice slow game and preferably a dynamic one where I don't know how the other factions will develop. I recently began modding files that I thought might help and at one time hit upon what I thought was a cure for superfactions. Alas, subsequent changes have nullified that effect.
IIRC i have edited the factions relations to be TOTAL LOVE all at -600 at the start of a campaign, I have removed all victory conditions, reduced the impact of the Population Growth Initiatives to all be 0.5% - all of these changes plus some others gave me a nice balanced game.
But I was not happy with the ease with which I could hold a newly conquered city. I wanted to remove all roman recruitment from any city that does not have an (L), figuring if they could raise a legion in the future, they could raise light infantry now. But that process seemed way too complicated for me so I have decided to merely add another house rule of recruiting a governor plus 8 light infantry in Rome and sending them to look after the new town. Oh, nearly forgot all of my cities have to have one spy and one assassin, so they get built and sent with that small army.
My latest attempt at making newly conquered cities rebel much more easily seems to have backfired due to me not really having a clue what I am changing in the files. I went into the descr_rebel_factions file and changed the chance to 9 for everything. This appears to have raised the levels of unrest to very high levels in a newly conquered city, but does not quickly (or quickly enough for my liking) spawn a huge rebellion army. This latest change has well and truly cocked up the balance I felt I had achieved for the other factions so I will have to have a look at it again.
From a gameplay point of view I have FOW off and have set pirates and rebels to spawn as infrequently as possible. The never ending tedium of hunting down small stacks of 3 units is more than enough to have me reaching for the ESC quit game.
To be honest I am having almost as much fun tinkering around with files that previously and often still make no sense to me, as I am slowly role playing my characters around the map. It's a pretty cool feeling when a change you want to make actually appears in the game and works as intended.