You'd think that after the Oblivion Crisis that a Lariat or two would make a play for the Ruby Throne with them being cousins of the Septims and what not.

What's going on with them in 4E? Still ruling Shornhelm? Are they even still around? Would they support the Mede Dynasty? Just some questions running through my mind as I plan a new game.

They probably did, but they were most likely beaten out by Mede when he took the Throne by force. By all accounts, there were plenty of people that started making claims to the throne after Ocato was offed, and the ineffectual bickering lead to no decisive heir being chosen since no one could comfortably secure control.

To be fair, there are a lot of people who you would expect to make a play for the throne in or after Oblivion, but who never do. If you recall in Morrowind, even out in the Empire's second-most-remote backwater you have pretty much everyone attached to an Imperial guild making plays for power, and Uriel isn't even dead (yet; everyone knows it's just a matter of time). But when Uriel finally does die, everyone just sits back and cries instead of doing something about it. Where are all those generals and Fighters Guild leaders that were planning to make power plays as soon as the opportunity arose? Where's the Elder Council? "At home," apparently; can't be bothered to return to the Imperial City even at the moment of crisis.

I imagine the whole "getting assassinated by Dagon worshipers to nearly usher in the end of the world" thing put a dent into many of their plans.