I don't want to be a game breaker, nor swallow too much serious pills here. But important for a museum is not to turn their place into a children's playground. That's not their task. With a bit of tears in my eyes I saw a couple of nice Dutch museums local here convert to such places. All technology ls stocked away into depots and they basically do not display much of the original technology backgrounds. "Kids find this boring", they say. But then I say: "Gleu a Mac Donalds aside the museum and let them play there!"
For people older than 16 there basically is not much to see. No real background, it is a playground. Really interesting items are hanging on the wall, high up, without sufficient interesting background. For a techie like me -at least- I recognize lots of things, but for most people it is 'abra cadabra'.
Am I child-unfriendly? No, not at all. I think that one of the main problems is to learn children to focus on one subject for longer than 5 seconds. *That* is what we should learn children first. The result will be that the museum does not *need* conversion to a playground: You can learn the child and you can learn yourself. And as soon as they get tired: Let them go to the Mac Donalds playground, leave one of the parents behind and dive back into the museum to swim & swallow into their beatiful technology ;-)
I still remember my trip to Science museum quite a while ago as the experiments on display were no less than pure magic. Things like pendulum balls, tube water oscillation, bubble traps were just amazing.
One fine museum that you missed is the Ann Arbor Hands-On Museum (www.aahom.org). Both kids and adults love it. I'm partial to it because I am the station manager for the museum's amateur radio station, WA2HOM.