In my opinion, the perfect storage box for electronic parts is the Plano 3750 (made in the USA). That is the box that came with the Propeller Education Kit, it has a combination of many small adjustable compartments and one full length wide compartment in the front that can be further divided if desired.
I have several other brands that are all the same overall size but none of them have that large compartment in the front that is so useful.
These Plano 3750 boxes are not so easy to find now. Amazon has lots of hits for the Plano boxes but in reading the reviews it seems that Plano is having at least some of their boxes made overseas and slapping their latches on them. Many of them do not even provide details on how the compartments can be arranged. I was pleased to find them on Zoro for under $7 a piece. Just search for "Plano 3750" and you will find them there. They also shipped very quickly, ordered Thursday evening - arrived Monday morning. Oh, and they come four to a case so it would be good to order in multiples of four.
There is a caveat, these new Plano 3750 boxes are made in the USA, and they are of high quality but... they are not the same as the old 3750s. They have beefed up the hinges, "improved" the dust seal and changed the front face. I could do without those changes because none of them increase their usefulness for my purposes. The pictures show how the front compartment has lost about 1/2" of useful depth to accommodate these "improvements".
I still think they are a good deal but I would welcome someone pointing out something better.