We desperately need to clear out the management team. Unfortunately, we have no football people on the board, so they are clueless as to what to do or to whom to turn.
But as a shortcut, I'd look at poaching scouting/player development people from Chelsea, Leicester, Spurs, Southampton, Dortmund, etc. These are teams that consistently identify talent with a good success rate, and they turn into players.
On the business side, we need to get rid of Gazidis. He's a parasite who has been underperforming from day one. Someone asked why United's commercial revenue is so much higher than ours - the answer is Gazidis isn't good at his job. And remember, United was doing this even when they were shit, so don't blame our lack of silverware for our commercial failures.
And it goes without saying that we need to sack Wenger and the entire backroom staff.
It's not unrealistic that we could do all of this simply by replacing Wenger's salaries with a new manager, director of football, and head scout. And Gazidis for the new CEO.