Luke, I certainly agree with returning to state legislative bodies choosing the senators. The states will always be the best check on the power of the federal govenment (and the power of the states will best be controlled by the people of the state - and by the constitution).
All of the talk about the popular vote for the president is nonsense. There is NO popular vote contest - each of the major general election candidates is engaged in an electoral college contest. They don't apportion their time or resources or efforts to win a popular vote. The focus on key battleground states that can shift the electoral college their way. If they were attempting to run a popular vote contest they'd do everything differently - the media/politicans/pundits are foolish to treat the "popular vote" numbers as if they meant anything.
Imagine an Olympic High Dive contest. The contestants know that the judges will give points based upon style and form and the chosen dive's difficulty. Then at the end of the contest some idiot says, "I think the contest results are bogus. The person who came in second should be the winner because they got the most applause from the spectators."
If I could make up a constitutional amendment that changed the nature of the electoral college it would be to go the other way. I'd have each state's House vote for the candidates and each state would be given, oh, say, 5 electoral votes - winner take all - that would be in addition to, and separate from the winner take all electoral votes from the state's population. So, Wyoming would get a total of eight electoral votes. Three that are determined by the popular vote (a small number because of their small population) and they would get another 5 votes from their state house of representatives (which might go the other way from the popular vote electoral votes). That would give more power to the partnership of the states that actually formed our federation - our "United States."
I'd also, on a different subject, like to see a constitutional amendment that created an FBI-like agency, but it would only investigate AND prosecute crimes commited by individuals holding national offices that are elected or appointed. And this agency would be controlled solely be a rotating board populated by, say, 9 state attorney generals. the federal government and its agencies would be prohibited from any attempts to control this agency. And it would be funded solely by a small per-capita tax in each state (no federal money). And each of the national office holders mentioned would have to sign a release of all privacy to this agency before they would be permitted to take office. And it would be a serious felony if any employee of this agency used any information they acquired outside of proper investigatory or prosecutory actions. That would "drain the swamp" - which Newt Gingrich was heard to say, "doesn't want to be drained."