Again, both redwood and Doug fir tend to be quite a bit denser than the wood I'd normally want for a Classical guitar. I've made several redwood topped Classicals, and they do sound good, but the added mass is likely to reduce the output a bit. WRC is often very low in density, which would tend to make it a better choice for a Classical.
"all these different conifer woods though, i dont think stand up to European spruce, which transmits sound faster then any wood in the world."
The speed of sound in a wood is simply a product of the density and Young's modulus: c^2=E/rho. Since wood is usually stiffer along the grain the speed of sound is different along and across the top. Also, this is the speed of a compression wave; we're usually more interested in bending waves, which are more complicated. The two are related, so knowing c is useful, but less diagnostic than it could be.
More to the point, though, there is so much overlap between species that it's not possible to make a blanket statement that one is 'better' than another in this regard. There is a close relationship between density and E along the grain which is the same for ALL softwoods, with surprisingly little scatter for a natural material. It's very nearly linear in the range of densities we see, too. This makes sense in that all softwoods share a very similar structure. If you want by statistical averages, Western red cedar tends to have the lowest density of the commonly used top woods, and given the normal relationship should have the highest speed of sound. It also tends to have a higher cross grain stiffness relative to the long grain than some of the others, and would gain there as well. Thus, if you want to make a generalization, WRC should take the palm among the usual suspects. And, of course, if you're talking about 'all the woods in the world', balsa should have the highest speed of sound.
European spruce does tend to have density that's only a little higher on average than Engelmann spruce, which, in turn, is just a bit denser on average than WRC. The spruces do tend to have higher surface hardness than cedar, which helps in practical terms. In the end, though, about the best you can say is that European spruce was probably the best top wood that European luthiers had to work with, so they used it. Since the designs we used evolved around the properties of the woods they had those are sort of 'built in', and tend to give good results by default, as it were.