a few amendments that come to mind at the moment, without delving into repealing existing ones:
-abolish electoral college and establish popular vote with IRV voting
-change senate terms to four years instead of six, giving each state the ability to vote in the senate every election (Class I in presidential years in all states, Class II in off years for all states--its always bugged me that in any given year 17 states have no say)
-abolish caucuses and fully closed primaries
-change the House to proportional representation (abolishing actual districts and just allocating that number of representatives to each state)
14. NO!!! The Electoral College is part of preserving our Republic against absolute democracy (America is a Repubic)
I never understood the "we're not a democracy, we're a republic" argument as any country with a president is a republic, be it a federal, direct democracy, dictatorship, etc. Democracy and republic are not mutually exclusive.