Make us able to pick two roles, but also tick that either is preferred, making both first/secondary.

Sometimes when I'm choosing my roles before a Ranked game, I feel like going mid or support wouldn't matter. But I have to put something as my primary role, and the other as secondary. So for example if I pick Primary Support & Secondary Mid (and I don't mind going either of these roles, hence both of them are primary in my head, but on paper it looks like I really want to support, and could possibly mid), then if I get matched with a support main only, we have a 50% chance each to get support, if both of us have picked mid as secondary. This is unfair, because to me I don't mind going mid at all, but the support really can only support and just picked mid because she had to pick a secondary role. This is where I'd want to be able to have a little box to tick that says "I prefer both roles equally" or something. Because I see this happening quite often, sometimes the toplaner picks top primary and mid secondary, when he mains both of those equally, while our midlaner also choose top primary, mid secondary, and she got placed mid because they both had choosen the same roles. Difference was that one guy had both roles as his primary, while the other guy really had one role as primary, and the other one as a secondary he hoped he wouldn't get.

Sometimes you don't feel like asking to switch roles so you just go with it. I think this little box you could tick would help managing roles better.

TL;DR: A box you could tick that makes system sorting roles better, where if you can play mid/top equally good, you can tick this box and let the system know you prefer either of these roles. Will make OTP toplaners that just happen to have mid as secondary role get top, and the other guy that can do top/mid will get mid.