I think "dice staging" systems are rather different than straight d20 systems, especially because the staging is not necessarily d4 to d6 to d8, etc. I've seen variants that, especially at the high end, go like, d12, 2d8, d20. The statistics on the roll is not necessarily flat, and certainly if/how the player searches for bonuses are going to be different. Looking for a +1 bonus on a straight d20 is not the same statistical change as a +1 bonus to stage you from d4 to d6.
So I was gone all weekend, but I wanted to come back to this thread. Originally, I was going to go into more of the mechanics of the thread (as promised at the bottom of the OP) but I was already going long and I wanted to give this specific topic time to breath. I think that the issue of choice of dice (and how they are used) is incredibly important mechanically, and it's something I wanted to discuss in terms of RPGs as a
game, and it's also something I think that videogames (with their focus on RNG) have looked at.
That said, the specific focus of this article isn't about the mechanics of the dice, or even fit-to-function of the dice. Instead, it's about the cultural assumptions (the semiotics, or signifiers) of the various dice that we use. I think that this has been touched on by some of the commenters already- for example,
@Enrahim2 notes that the choice of dice might be a signifier of the type of game- something I am generally in agreement on (I phrased it as "indie games").
@MNblockhead ... perhaps jokingly ... mentions that the platonic solids are a good fit for the fantasy approach because they impart an alchemical feel. I hadn't thought of that, but it's true that there is something to it.
Perhaps a bit of personal history that I elided would help. I've been designing a lot of rules-lite games for personal use lately, and between that and some FKR games, I've noticed that I've been designing a lot of d6-based games. And I started to wonder ... why? Why am I doing that? I have this giant arsenal of dice, but every single time I sit down and make a quick adventure, I
always default to some modified d6 system.
It's definitely not because I like the d6- I don't. In my "love of rolling dice," I rank dice roughly like this-
d12 > d20 > (d10 = d6) > d8 > d4
And it's also not because of fit for use. I think that there are times when, at a minimum, a d12 mechanic would probably work just as well (if not better). So why?
And the brief answer is ... because
that's what people do. When creating a rules-lite game, when making an indie game, you use a d6. On the other hand, when you're making a "big game" or a "giant commercial game" you go for the "big set o' dice," or, a at a minimum, more than just the d6 (d10 at a minimum). While there are some exceptions, that's a pretty good rule.
This first initial post is getting people to discuss that (and, perhaps, disagree with that) before moving on to the specifics of different mechanics- why some games might have a better use for different dice.
In short, after this initial post and discussion, I'd like to dive more into the nitty-gritty of the dice mechanics of different games- the "game" part of the RPGs.