Surely you have some favorites (either to eat or to make) from previous years - what recipes are on the top of your list?
For Mr Cat's office, consider some sugar free spiced nuts for the keto/paleo crowd. If it's a leave-it-in-the-breakroom situation, maybe some sort of divided tray nicely arranged. Or a bakery box with parchment paper dividers. 75 small pieces?
How many people will the other gift baskets serve? Might be better to use small treat bags for those to keep things fresh and separate. Nashville Wraps has some cute festive gift bags that are heavy duty - something like this with a sheet of colorful tissue and assorted treat bags would be easy. https://www.nashvillewraps.com/bags/printed-gift-bags/p-672/ptjmco