It seems like Supports in Season 6 are getting less experience than they have in the past, and it feels like a real problem. As a support main I am very often 3-4 levels below my own AND enemy solo laners, **regardless of if we are winning or losing**.
All support champions scale well with levels because they rely on skill ranks and base values for their stats. Being four levels down on an enemy champion means you are at a distinct disadvantage, even if your team is ahead of them.
Watching professional play, the pro supports are suffering from the same effect, but even worse because pro supports roam so often. Watching a lvl 13 Alistair attempt to engage a lvl 18 Kalista in EULCS today made me cringe. Sure, his skills still work, but he can't act as a tank when he's so far behind. What good is being full item build if you cannot even get lvl 16 in a 50 minute game?
Riot has done an admirable job with getting supports the gold generation and items they need. Now I think it's really time to look at experience gains and see what can be done to make sure that supports don't fall so far behind. I am not saying they need to be even with the midlaners, but 1-2 levels down is a reasonable expectation. 3-4 levels down is NOT.
What I propose is that either Sightstone OR the support items gain a new passive: "When near an allied champion of a higher level than you, gain X experience per 5 seconds." Yes, this might look familiar, it's the very useful mastery from the old utility tree that was cut when the new masteries were put in. Give it back to us and tweak the numbers to make it fair, and I think the game would drastically improve for support players.