Well, the pre-1808 lineup was for the House to choose between the top five EV getters, except in case someone won an outright majority (which was considered unlikely after Washington's retirement), and for the top EV getter - or no.2 if the top EV getter happens to get elected president - to be VP. It was a compromise between those who wanted the EV to choose the President and those who wanted Congress to do so. In fact this compromise is the chief reason the VP office was invented.
So it does make sense that eve post-1808 there's less room for intracongressional intrigue in the selection of a VP than a President. It's the Popular Mandate position.
Also pre-1808 had the Senate choose the VP if there was a tie among the top remaining candidates after the President was chosen, which is probably why post-1808 the duty remained in the hands of the Senate in the new system if eth EC didn;t produce an outright winner.
