Why Is Bottom Lane So Important? Simple Statistics

When the Jungler (or Mid) ganks Bottom Lane, 3 champions get gold if the gank is successful. Every other lane, only 2 champions get gold (unless both the Jungler and Mid gank said lane, but you can apply the same to Bot and then 4 champions get gold). Furthermore, Dragon is in the Bottom Lane and, due to how easy it is to take Rift Herald and Dragon each, the Jungler doesn't have to dedicate themselves to getting Rift Herald. Plus, you only get one Rift Herald to focus on, so you have the luxury to take Rift Herald any time before the 20 minute mark. However, with Dragons, the earlier you focus on the Dragons, the more boost you will get before the Elder Dragon starts to spawn and then the Elder Dragon will multiply that boost by 2x, so focusing Dragons essentially increases your team's scaling while Rift Herald is a one time thing, unlike Herald which is a one time, get it as you please as long as it's before 20 minutes, that only provides a one-time boost to pushing a lane, with a well timed Rift Herald usually meaning your team gets 1 tower, 2 if you use it at a REALLY advantageous time. Dragons don't really matter when you take them as long as you CAN kill the Dragon, since they simply provide a permanent boost to your team.

Simply put, Bottom Lane will ALWAYS be the best lane to prioritize on unless either the meta creates an absolute monster of a top lane champion or Rift Herald becomes a similar monster to Dragon that is more about permanently boosting your team's scaling and acts in a way that snowballs off your team getting as many Rift Heralds as fast as they can, like Dragon. So, in conclusion, here are the ways I can see Riot making Bottom Lane less of a "must prioritize" lane:

1. Make Rift Herald spawn multiple times and not share the same spawn point as Baron Nashor (big map edits required)
2. Change Dragons to instead spawn at set times instead of having a respawn time (this way rushing Dragon doesn't make you get the next Dragon any quicker)
3. Remove or heavily change Elder Dragon so that it doesn't multiply the stats you obtained from Dragons
4. Change how Bottom Lane turret fortification works and/or make Top and Mid easier to push
5. Simply make Top and Mid Lane champions much better at carrying a game and/or reduce the carrying power of Bottom Lane champions (some want this, but I think this would warp the game and champions in unhealthy ways)
6. Essentially make Rift Herald and Baron Nashor mirror Dragon and Elder Dragon mechanically, but be PvE objectives instead of Dragons PvP/Player Enhancement objectives (would likely require heavy reworking of what both objectives provide)

Riot can choose one or more of these solutions and that would make Bottom Lane less of a deciding factor in the game.