I think the reality is that there is no one answer. Some bands will do better staying as faithful as possible to the original. Some bands will do better putting a significant spin on the tune to make it their own.
I see two problem areas that bands get into, in my opinion:
1) The 'spin' they put on the tune isn't due to interpretation/creativity - it's more due to the fact that they didn't actually learn the original version to begin with, and just do it halfway.
2) They 'spin' every single song to the point where it just gets silly. It sounds like a cheesy gimmick after a while. Classic example is the power trio type thing where every song turns into a reggae inspired version. Please just kill me now.
I see two problem areas that bands get into, in my opinion:
1) The 'spin' they put on the tune isn't due to interpretation/creativity - it's more due to the fact that they didn't actually learn the original version to begin with, and just do it halfway.
2) They 'spin' every single song to the point where it just gets silly. It sounds like a cheesy gimmick after a while. Classic example is the power trio type thing where every song turns into a reggae inspired version. Please just kill me now.