We've always done mixed boxes, 3 different boxes, each one out in the living room for 3 weeks then rotated to the next
If he asks for something that's not out I tell him it's not currently in rotation but he can have it in a week / 2 weeks and he's happy with that
Each box currently contains 8 items (including a musical instrument, puzzles, a game, construction toy, role play toy, ball etc) and he has access to 1 larger physical toy eg trampoline per rotation.
Always available are his kitchen & play food (stored inside his kitchen), his torch and 2 wooden spinning tops in his bedroom, a box of lego and some small cars in the living room, and some art & craft stuff in the storage unit in the conservatory.
After playing with one toy we encourage him to put it away before getting another one out. If he's made a mess everywhere he has to do 'tidy up time' the same as they do at nursery (we help a bit if he needs it).
He plays with his toys very well so I think we've got the balance right
Remember with a toy rotation less is more!