Make sightstone cheaper
Benefits are: 1). Let supports go into their builds a little earlier. 2). Introduce more interesting decision to non-support roles. This will introduce an interesting strategy option for non-supports -- do I buy sightstone? Right now the answer is pretty much always "no". It would be more interesting than if occasionally (for example if very behind) the answer could be "yes", opening up vision control game for non-support. Riot does not want non-supports to regularly buy sightstone (judging by its price-benefit balance), and it is all good -- we don't want every katarina running around with one. So price point should be such that non-supports still rarely buy it (but occasionally do -- interesting strategic decisions!), my guess is around 650 gold will do it.
P.S. I do not queue for support (only playing it when autofilled or someone else on the team badly wants to trade), so this is from non-support perspective. But I do not see how this change can be bad from support's point of view.