I have this problem where I continuously drift between Top, Mid, and Jungle. I like solo lanes because my performance is almost exclusively dependant on myself and not linked to a lane partner.
Usually I'll go after mid or jungle, but when I have some really good games and start playing even more aggressively than I do already in mid or jungle, I seem to draw a lot of attention from other lanes as well as the jungler, it gets kind of annoying, so I'll go Top lane and do the same kind of stuff there. Top has always been kind of it's own island and I rather enjoy that sometimes as there's little interference with my game until laning phase is over.
For mid I tend to play primarily assassins, I got quite good with pre-rework Fizz, LeBlanc, Kassadin, Talon, Zed, Yasuo, Katarina, and at one point Diana. That list has now dwindled primarily to LeBlanc, Talon, and Zed, who I think I'm now very strong with. I'll occasionally get a mage craving and run Viktor, Orianna, or Malzahar, but mostly assassins in my mid lane.
For Jungle I like mostly tanks, so the new jungle item made my day, I'll run Sejuani (nerfs incoming unfortunately), Volibear, Nautilus occasionally. I also came to very much like Nidalee jungle, not because it's OP necessarily, though that doesn't hurt, but because it's a different flavor than the rest. Rek'sai and Kha'zix are two others I enjoy now and again as well.
Top lane I play almost exclusively Riven, with the occasional Renekton thrown into the fold. Both just offer a lot of outplay potential, Riven I can comfortably 1v3 when ahead a little, Renekton I often turn a gank into a double kill, just a couple champions who discourage ganks from a jungler, and don't really even want ganks from their own jungler. Both also reward my aggressive playstyle.