A system for proposing where and with who you would could do well with.
A system that gathers info from your recent games and makes a prediction as to what role and what champion would best suit your play style. This would be an ongoing thing that would update regularly. This would be used mainly by under level 30 players since they are just learning the fundamentals and are not paying a lot of attention as to what they do best at. This would be bias towards who you played recently, but it doesn't mean that role or champ is your best. The system would have to take info that is not specific champion or role based, such as build items chosen frequently, or farming skills. If anything it would at least be interesting to know what Riot thinks you would do well at. Maybe it could also tell you where you need to improve to fit your current favorite role.
You could even spend IP to have it check the next 5-10 games as its sample (for people who have excess IP).