Kids are now 8 and almost 5. When they were small, the playroom was wooden toys and books on shelves, full sized playhouse in the corner, sofa and plastic tat in my old toy cupboard.
Now the shelves are a shrine to playmobil, lots of board games and a table to play them on plus non fiction books and all the non farm/dinosaur Schleich/Papo. There is a Tv and gaming console but the xbox is in the family room. Toy cupboard houses craft materials and more playmobil. Shelf full of craft books.
In dc1's bedroom he has a desk for homework, his nerf gun collection, lego, a wooden castle and knights plus large box of dinosaurs.
Dc2 has a wooden dolls house, a Barbie house, a wooden farm plus animals and a "dressing" table that functions as a desk in hers.
If they both have friends around at the same time they like the Family room for the big tv/xbox or the playroom for the playmobil. If just dc1 has friends, then they play his room for a bit and then game. Dc2's friends like her room.
Playroom storage is mostly Billy bookcases with a Kallax unit and my childhood toy cupboard plus a table with storage built in and a surprisingly comfortable sofa bed.
I like things in tubs, ideally with lids on shelves so they can be moved around. For example the duplo mostly lives in Dc2's room but it can be easily carried anywhere in the house. We have some slippage like the odd escaping Barbie but mostly toys stay in their proper locations.