Do any serious teams need a player?

I have been playing for half a year and I play every day. I am only missing 20 champions so trading in champ select shouldn't be a problem. Now two problems I have are that I don't have a main like other people do, I just play a lot of champions and fit to the team, I have gotten advice to get a main and I tried but I just end up getting sick of the champion. I can play any role, I main(ed) mid and I have been working on my top lane, I still need to learn all the ins and outs of being a good jungler, and for bot lane... well I can adc decently in lane, but during teamfights I have no idea what to do as an adc, also I can play thresh support but I am not good with warding. I really like playing assassins but I can play other things just as well. I am willing to practice and play anything you want me to, I would like to join a team so that I can get much better than I am now. If you are wondering about my division... well I got silver 4 out of my provisional matches but then they reset ranked at season 4 so now I need to complete them again, I have done 7 of them. Oh yeah, and my username is dragonizerx.