I've seen it mentioned a few times already, so I'll just echo my sentiments. I would like to see URF become a custom game mode:
In my ideal version, there would be no bans, you can pick the champions your opponents pick, and you can even pick champions that have already been chosen by teammates.
Do you want a five-man Master Yi URF team?
That's your choice, have fun with your decision!
The point isn't for URF to be balanced. The point is to let players have as much fun as they desire in an unbalanced sandbox where everyone gets what they want and has their restrictions drastically reduced.
There is one change I'd make to how gold is obtained: All gold earned (except from champion abilities / passives, runes, and item passives) is shared evenly between your participating team. Teammates who have not moved their champion for 4 minutes are considered idle, and gold will not be shared with them. on the third time this happens, gold is not shared with them for the rest of the game.
Gold sharing would encourage the team to cover objectives and participate in takedowns. If a player is outperforming their teammates, their shared wealth helps everyone progress through their builds at the same pace. The exception are players making use of bonus income sources, who will progress faster as a result of those additions.