It works financially, but Brown is a #2 type guy. You could go through the NBA and make a list of players, and put them in certain spots.
Some are #1 options, some #2 options, etc. Like Klay Thompson - excellent #2 option but wouldn't be great as a #1. Much like Pippen back in the day. Just better as a #2. Russell Westbrook is a #1 who doesn't know how to be a #2 or #3.
Tatum is a #1 option. Donovan too. In my opinion, Brown is a top end #2 option. I don't think Brown would take charge and lead like Donovan has in the playoffs. While he is a much better defender, he's more of an all purpose guy to support every aspect of the game while the #1 guy focuses leading the team on offense down the stretch.
Nobody here wants to see it, but Rudy for Brown makes the most sense. Boston and Utah are both more realistic contenders after that deal. Donovan and Rudy don't compliment each other very well at all.