As already mentioned, there is no one correct way to pan drums.
It has to do with so many different factors.
It depends on how the drums were recorded most of all. An XY overhead position will give you a much different sound than a spaced pair, as far as width is concerned. (The same goes for any other overhead mic positioning.)
As far as toms are concerned, there are other things to consider as well. Sometimes, a basic rule of thumb is to listen to the overheads in solo and to pan the toms in whatever positioning you hear them in the overheads. But, that's not the only consideration, IMO. Toms are very rarely the most important element of a song. Therefore, other instruments should take precedent. For example, if an important guitar part is panned 25% left, and that's were you'd normally pan your tom. You may want to reconsider the tom's positioning to further get it out of the way of that guitar. Also, the way that the toms are being used in the song come into play. If they are being used to play fast fills, you will want to make sure that the sound from one tom to the other is very fluid. If they are being used more sparingly, you could more than likely afford to pan them out wider. It may not sound as natural. But, "natural" isn't always what we're going for.
As far as kick and snare are concerned, I typically don't get too experimental. I'm not saying that it is wrong to get experimental. I just haven't yet mixed a song in which panning a kick anywhere off-center has seemed appropriate. I have mixed a song, however, in which a drawn out, military-type, snare roll in the bridge began on the far left of the soundscape and gradually made its way to the center. But, other than that, kick and snare typically remain up the center for me. But, feel free to get creative.
All of that being said, I also typically pan according to the drummer's perspective (unless the producer or artist requests otherwise). Basically, my only reasoning for that is the fact that I mainly listened to Incubus albums when learning to mix. And, their drums are typically mixed from the drummer's perspective. I know that's not the world's best logic. But, most casual listeners won't notice anyway.
I have heard albums in which one song was mixed from the drummer's perspective, and then the next was mixed from the audience's perspective, even when both songs were mixed by the same person.
Also, hi-hat is often a topic of large concern when dealing with panning issues. This is an important one. And, to me, the song completely determines the placement of the high hat. What role does the hi-hat play in the song? Listen to the hi-hat up the middle. Listen to the hi-hat panned far off to one side. And listen to the hi-hat at every position in between. Listen to how it carries the song. Sometimes, too wide makes it almost distracting. Sometimes, based on the vocal line, the hi-hat gets buried by the vocals if in the center. The hi-hat is often a very important part of the song. Other times, it play no significant role. Pan it accordingly.
Again, there is no one correct way to pan drums. If you're mixing a solo drum performance, then that's one thing. But, that's not what I'm talking about. We're mixing a SONG. And the song is the #1 factor in mixing. When mixing, actually THINK about what you are doing. Don't expect some formula to give you great results every time. This isn't mathematics. It's mixing. The reason I do it is so that I can be creative. Every song is different. Treat it that way. I know this isn't necessarily the answer that you wanted to hear. But, it's the truth.
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