Did Season 2 of House of Cards disappoint anyone?

Spoilers below....

As realistic as the first season was in its portrayal of Washington and its politics (the passage of the education bill could happen exactly as it was shown), some of the plot lines in the second season just seemed so ridiculous.

How many scandals can a Vice President and his wife be involved in and survive in just a couple of months? Abortion, Rape, Raymond Tusk, etc.? It was never clear to me why Frank went after Raymond Tusk as hard as he did (the only explanation he offered was some bullshit about the wind blowing too strongly from the west).

The whole Raymond Tusk vs Frank Underwood saga was like...come on. How can the president who has leaned on Tusk for advice/mentorship for over 20 years just abandon him after one mistake when he very well knew FU was perfectly capable of lying through his teeth to get what he wanted? How could a President be so oblivious to such a high profile war between Tusk and FU?

Lastly, how in the world can a president let go of a Vice President and Chief of Staff less than two years into his presidency? He'd be a laughing stock of the entire country. The more I think about it the less all of this seems even remotely plausible.