The Squad Plannwr is a lesser implemented Squad Depth screen. It's the exact same thing but you can add a player rather than them automatically listed.
If you have players on trial, they are not added. So if you're a smaller team trying to snap up multiple free transfers via trial, which gives you deeper star ratings and coach feedback, you have to add each individual player one by one by one to every single position. If you then ask your assistant to list players by rating, saving you several minutes of manually moving players one by one again, they disappear completely. It is In general a largely pointless rework of an already existing screen.
Lollujo, one of.the big four FM streamers discovered this on stream and it basically meant he had to go via the old school route of comparing players, rendering the screen pointless. If you've experience with the game anyhow you'll have targets in mind and know which youth are worthwhile in the space of a two minute glance.
The one area it would actually improve, International Management due to the huge player pool...well it doesn't exist. You do not have that screen for it.
I could go on and on and on and as mentioned above provide examples for everything wrong with this, but if you cannot see the problems with defence at the very least in the ME you must have a blessed beta mate. It's utterly shambolic.