I would say your numbers are a bit exagerrated when it comes to the amount of Democrats who support gun control. I will ask the question you like to ask which is "do you have any facts to back that number up?" Also, if you are a libertarian by ideology then I can't see how you can agree with many of the Republicans views at all. Finally, I have no idea where you are looking to see a night and day difference between elected Republicans and Democrats. The last several presidents whether Republican or Democrat were progressives and globalists along with many of the leading politicians in each party. I realize on this board it is "bad will" to talk politely about the Democrats but if you take the blinders off you will see that both sides are equally wrong in so many ways.
You're right, after some quick checks on a few bills it's more like 75 to 88%, depending on the particular issue. I don't think this affects my thesis, especially when you consider that on some votes, when there's enough to go strongly one way or the other, the party leadership allows a particular congressman to vote against the party in order to shore up a record that can be used in the next election.