Idea: Rift Herald buffs your summoner spells
Rift Herald is pretty much useless to do over any of the dragons. But I think Rift Herald would be more worth if it buffed your summoner spells. That way top laners who roam with TP will have a better way to help their team. Or if they take ignite it does more damage per tick and lasts longer, and flashes range is increased by a certain amount.
I'm not sure how much this could affect the game, but I think this could bring a lot more summoner spell diversity in the game and Rift Herald and top lane wouldn't be completely abandoned the whole game.
I don't really know what they would do to balance it, but I think this could make League more fun and more of a team game. Bot would have to go top to take a Herald early on and it would actually be worth it, and it would be easier for top to participate after getting the buff, or just give it to the fed person to make them stronger.