Keep in mind a couple of things, please. First of all - this is NOT merely a situation of taking the best overall rating of an album and subtracting ten (from its decimal equivalent), as on the (old) Starostin site. I do regard evaluation of an artist based on its peak output as the best way to go for evaluation, but I also believe that it's possible for a band that's not rated 5 *'s to make a virtually "perfect" album (this has happened twice).
Second of all, while I initially felt that factors such as consistency were important in determining a band rating, over time I have decided this is not the case. While it's acceptable if a group puts out several decent and good albums but has trouble getting to "the next level," the fact remains that the group could NOT get to the higher level. As a corollary, while it is possible for a band to get a lower band rating than suggested by the best album, it is NOT possible for it to get one higher.
And finally - I do not care about the influence a band has had on other groups when it comes to the rating, nor do I care about any factors aside from the grades I give to the band's three best albums (and so it's clear, I do not fudge the album ratings to ensure a specific band rating). The band rating is an indication my feelings towards the albums a band did, and while factors such as influence may have some weight in determining the grades of the band's best albums, they will not influence the band rating beyond the influence had on the album ratings. In other words, as an example, I don't care if Led Zeppelin is the most influential hard rock band ever; they aren't getting more than a 3, and that's that.