iv skated conical fulls, classics and radial slims. so not quite conicals i guess, but i found the contact patch on classics to be a tad too slim, and the conical fulls were a bit too wide for my liking. radial slims were a pretty good halfway point for me. so i'd get that and go from there depending on how you like it, and if you want something slightly wider than that, conicals are good.
edit: i find it way easier to slappy on classics, like a lot easier than on conicals or wheels with a straight edge, however the corollary to that is that classics don't lock in to ledges and round rails as well, easier to slip out of 5050s on round rails. then again im shit at slappies