I'll admit up front that I'm a yellow dog Libertarian. I vote straight ticket Libertarian in every election, and I vote for Democrats and Republicans in races in which no Libertarian is running. If you really believe in your own party and what it stands for, then the straight ticket button in the voting booth makes the process quicker for you and the people standing in line behind you.
Opponents of the straight ticket option want voters to research the individual candidates instead of just blindly voting the party line. If that is the goal, then party labels should be removed from the ballot altogether. A lot of people will still vote for their preferred party's candidates, but at least we can make them research ahead of time who their party actually nominated.