I think Queen is the best band because:
1. the vocals
2. the songs, they cover Noah and the flood to a poor boy about to be sent to death row to girls with big butts.
3. every single member was good at what they did and every single member contributed heavily. A lot of the most popular Queen songs (Another One Bites the Dust for example) were done my John Deacon, and while he wasn't much of a singer, he was a killer at song writing and bass. Brian May is top 10 best guitarists in rock. Roger Taylor is a top 10 drummer, and wrote (AND SANG) multiple songs himself. Don't have to say shit about Freddie. They are such an even band in this regard. Other bands, usually they tend to have like one or two song writers their entire tenure and it feels less of a group effort.