GBA SP and DS Lite were my favourites.
Can’t say I can think of a worst one. Just something that wouldn’t be in the market for me… something like 2DS, probably - as the idea of it felt like Nintendo giving into the moronic anti-3D paranoia. That said, the 2DS would be perfect for kids with paranoid parents who bought the whole “3D causes seizures and eye damage” narrative and didn’t want to buy their kids a 3DS.
I describe myself as a little dose of toxic masculinity.