As a male Nord (not a Dovahkiin), I would live in Riften as the Guildmaster of the Thieve's Guild after having helped the Empire win the civil war against Ulfric. Also, even though ingame, I am part of the Dark Brotherhood, I would not join it if I lived in Skyrim because of my pesky conscience
.
I would live in Riftweald Manor with Brynjolf, my husband with the rather hot Scottish accent. My main goal and first iniative would be to have all thieves in the Guild stop stealing in Riften. Without the Thieve's Guild stealing in Riften, conditions would slowly grow better. However, I would make the process happen faster by taking a sizeable chunk of all profits and distributing it around the city. This would increase people's favor of me and would make Riften a thriving city. I would convince any unsure members of the Guild (or Maven) that not stealing in Riften would benefit everyone in the end with the Amulet of Articulation.
Any thieves of the Guild caught stealing in Riften would be immediately booted out of the Guild. In addition, all information on said person would be distributed to the guards and Maven (now a Jarl). They would be commanded to arrest the thieves on sight.
I would venture around Skyrim with Brynjolf in spare time, establishing the Thieves Guild further even beyond Windhelm, Whiterun, Solitude, and Markath. This would gain more profit to make up for any profit lost by not stealing in Riften. Vex and Delvin would preside over the Guild while I was not there.
As Maven grew older (it has to happen) I would slowly start to gain more of her trust, take over Black-Briar Meadery. This would be easy, as I already have her trust as a Guild Master. Also, she only has a husband and two children.
Hemming, her huband, doesn't have nearly the pull Maven does. In addition, as her husband, that would make him about as old as she is, if not older. This would shoot down any hope of him becoming head of the meadery. As far as being a Jarl, according to
http://elderscrolls.wikia.com/wiki/Jarl, the position of Jarl is passed from parent to child, so Hemming would not be in the line for the throne.
Sibbi, her son, is, as even Maven herself admits, spoiled rotten and immature, unfit to serve as Jarl or head of the meadery.
Ingun, the only Black-Briar other than Maven to have any sense of responsibility, is uninterested in and even dislikes her family's line of business.
With no one in the Black-Briar family able/willing to lead as Jarl or as head to the meadery, Maven would likely transfer both positions to me (especially as Jarl because of my support of the people of Riften in addition to being a Legate in the Imperial Legion).
After moving into Mistveil Keep with Brynjolf (and buying Ingun an alchemy shop because I think she's cool), I would then appoint Hadvar (awesome
person) as my bodyguard,
(SPOILER) Karliah
(SPOILER)as my steward, and Enthir as my court mage. I might appoint Dirge as my bodyguard if it turned out that Hadvar wouldn't be able to keep me being Guild Master
(SPOILER) or a Nightingale(SPOILER) a secret.
I will be a fair Jarl, keeping all skooma trade and crime out, winning the support of the people even more, and expanding Riften's walls.
While this is happening, the conditions of the other cities of Skyrim will be decreasing due to rampant thievery while the money from said thieveries improves the city of Riften. Also, more tourism would be in Riften, helping the economy, and more thieves would be attracted to the rich city, leading to more oppurtunities for recruitment. Elisif or the then-High King/Queen of Skyrim would probably die in the next 5-10 years while Riften continued to boom and prosper.
I would then most likely be elected High King due to beeing both a war hero and Jarl of the most prosperous city in Skyrim.
As High King, and probably in my late 40's or early 50's at that time, I would live in leisure for the rest of my days, continuing managing over Skyrim, Riften and the Thieves Guild.