Should support/fill players gain extra reward?

Chances are, they won't be able to do that, without breaking their carefully crafted reward system. Basically any reward small enough to not break their system, won't be a strong enough impact. (if they just sicked to IP rewards, it would exclude anyone who already has all the champions.)

Right now, the main reward you get is simply shorter Q times. (which is fine by me) But a lot of people simply feel like they become obligated to take that role if they want to play. And currently, Riot is probably banking on that Hexcraft system. ("Cause for each support you have, there's a chest waiting to be unlocked.")

The obvious fix would just to make supports feel good to play. But I'm afraid that Riot may not be able to actually do that without breaking the class. (If you won't play support because you can't carry/impact games, don't complain about Raka/Sona/whatever.")

The real problem with this is that you will get more people who q as a support, but pick MF or some such and dont build a sightstone

I'd rather have supports be able to make meaningful contributions to the team.

But yeah, until they're fixed, extra IP would be fine.

I think if itemization for supports was fixed, things would be different and people would enjoy the role. As it stands, the main items in the role are excessively passive in terms of what they do and don't actually offer much to the support aside from really nice activates. At least everything but the Frost Queen. Face and Talisman just have defensive stats, and even then, they don't offer straight defenses, just regen and HP. If Face offered bonus Armor or MR, it would potentially be a great item for tanks that flow into their kits. For the Talisman, I'm not sure what it needs. I haven't seen it used in quite some time, but it definitely needs a boost. Additionally, the Sightstone also suffers in that it has horrible build options. Again, the most it offers is more HP, which isn't a stat that offers much to the kits of many Supports, and the combination gold income items are just blah. They should consider removing the Sightstone from the items and instead reworking the warding trinkets. Perhaps binding the Trinket to the gold income item to have it become a special Sightstone would be better, and free up both space and money for the support to buy more scaling items faster so they're not always strapping for money and behind on everything.

The reward is generally shorter queue times.