Hmm . . . the arc backend on master doesn't use `opts`. So do you mean that it's nicer to leave it on in case a different backend were to want to use it?

Also, the way style works on this branch, it just throws a `@style.merge!(opts)` at the end of `style_init`. That means every `opt` is accessible via `dsl.style[:opt]`. 

So in the 'opts are styles' paradigm, we are sorta having the front end stick all the opts on itself (with style picking up the dregs) and then if a backend (or anything else) wants some property of the element it either has to do (using wedge as an example) `dsl.wedge` or `dsl.style[:wedge]`. But it should never *need* to see opts explicitly. . . not that I'm against it, I'm just probing for understanding. :)