You need a Cybiko, Game.com, NGPC, Gameboy Pocket, PocketStation, Turbo Express, and Gamepark 32 to round out that collection. I'm sure you had a VMU, and I won't count the Game & Watch against you, because there were so many (and I'd also have to count other single game units).
I had a gameboy pocket , I have a ngpc too , I have a game.com , I have a turbo express .
Not sure on the pocketstation
Don't have a gamepark 32 nor a cybiko
I do have some game and watch ones . I have the clamshell one like the ds where you had to catch the eggs before they cracked .
I also have the nintendo watch from back in the day . I also have 8 vmus hehe