31 from the US , 14 from Germany, 14 from the UK, a decent number from Poland (maybe 14ish), and a handful from Norway, Spain, and the Netherlands. Probably 80ish if everyone comes through. So maybe a brigade plus a few squadrons.
The US uses a nemonic called DOTMLPF; Doctrine, Organization, Training, Materiel, Leadership, Personnel, and Facilities to analyze the impact of a change like adding tanks to your inventory.
Changing your materiel (adding M1s) has impacts on doctrine (how do you manage ammo resupply, maintenance, etc.), training (training crews and mechanics), materiel (repair parts, ammo, etc.), personnel ( trained on the M1), facilities (for depot level maintenance).
Now, add Leos and you have the same issues, but for a different system, different maintenance procedures, different training for crews, maintenance personnel, etc.).
Then add British Challengers.
Now you see the complexity of adding a small number of a bunch of different weapons systems.
I'm sure the Ukrainians would love a large number of the same system, but they are not in a position to be choosy.