Status
My hot-take
Connington: Moderate
Con:The Stormlands are weaker than the Vale, Westerlands and Riverlands, which are reckoned to be able to muster 45000 men [the Stormlands are thought to muster 35000].
Con: You can expect Renly and Cersei to try to overthrow you, and they're two of the most charismatic people in the setting, with Tywin's support, who is the most strategic/powerful.
Pro: You can rely on some support from a range of loyal houses and have good standing in king's landing.
Darry: Hard
Con: The Riverlands are going to suffer grievously in any civil war scenario, putting you on the front lines of every conflict.
Con: The Tully legacy looms over you: cousins may one day seek to regain their lands and titles, with Lysa and Catelyn posing the obvious risks.
Con: With a range of upstarts, belligerents and Tully loyalists in the Riverlands, your lands are likely to be tumultuous.
Pro: You can rely on good standing with the crown, having shown unwavering loyalty in the past.
Rhoyce: Easy
Con: Littlefinger is lurking about, probably.
Con: Your House seems to have inherited the Protector of the Vale title by default, and your house lacks a close relationship with the crown.
Pro: Your lands are easily defended, and you lack rivals within the Vale, giving you an excellent defensive position.
Pro: Lysa's bloodline will inherit strong claims and significant sympathy within the Riverlands, if the Darry's can be undermined at court.