A Monkey Village with Radar Scanner is useful because it's very likely that in the later rounds you'll lose your lives from camo bloons.
If you are playing on BTD5 Deluxe, on BTD5 Steam, or on BTD5 iOS, it is recommended to buy Monkey Engineers, as they can build Sentries along side with the tower to help defend the bloons. Don't forget to buy a x/2 Monkey Village or 3/x Monkey Engineers for the camo and lead bloons!
As Round 63 is approached, it's best to prepare to get 5 Super Monkey plasmas or an Arctic Wind and Monkey Intelligence Bureau. There will not be any camo bloons in Rounds 63 to 69 because on Medium, players only need to complete at least Round 65 to pass.
Using at least 2 farms up to 4/2 can be extremely beneficial, especially when the time comes to sell them.