Sorry, couldn't resist the wurst pun temptation.
Back on track, though, assuming there is such a track: I have heard that the best ways to measure executive effectiveness is to look at how well the president is able to broker compromise in congress, and also if the president is re-elected or not. Meaning- Jimmy Carter and George HW Bush are good candidates, and Gerald Ford is an excellent candidate (since he was never elected in the first place and then lost re-election) for worst president.
Interestingly, Quinnipiac polls seem to bring up a dichotomy - the presidents ranking near the top of the list for "best" are also near the top of the list for "worst."
Most recently:
Best Six:
1. Reagan
2. Obama
3. Clinton / Kennedy (tie)
5. Trump
6. Eisenhower
Worst
1. Trump
2. Obama
3. Nixon
4. Carter
5. GW Bush
6. Clinton
And the older poll:
Best Six:
1. Reagan
2. Clinton
3. Kennedy
4. Obama
5. Eisenhower
6. Truman
Worst
1. Obama
2. GW Bush
3. Nixon
4. Carter
...
So, it looks to me like Bush hate has simply become Trump hate, and Clinton hate has become Obama hate. Same goes for love.
On the other hand, Carter, who lost re-election, and Nixon, who resigned amidst controversy, are universally viewed in these polls as a bad presidents, but the amount of hatred for them amongst the general population is eclipsed by the more recent flavor-to-hate-of-the-week.
Oh, and Taft lost re-election, too, only managing to win Vermont and Utah, which is pretty embarrassing for an incumbent, especially considering that his successor was not very popular at the time.