Not sure if this will help, but I thought it was worth sharing. After years of attempting the same thing, I've found that the reason box always ends up too heavy or cluttered is that I'm trying to fix everything out of one box.
In 2012 I finally broke everything down and was fortunate enough that I had duplicates of tools to do so.
I have a few 17" Craftsman hand boxes that are all job-specific. One for plumbing, one for electrical, one for masonry and one for automotive. Sure, it's a little more expensive to have redundancy in tools, but grabbing one box and not having to spend time putting together everything I need to change a light switch or replace a sink trap is great. None of those boxes are filled with Snap On stuff either- it's all home owner level stuff.
We're in the middle of a move, so I can't get a shot of the boxes on the shelf right now (can't wait to get in my new garage!).
I do a keep an 18" DeWalt bag filled with a big enough compliment of tools that I can grab it and go help a friend, supplemented by the small bag I have in the cars.
Sure, there are a lot of tools floating around and my nicest stuff stays at home, but nice to me is an Armstrong ratchet. I'm not a pro and will never need anything bulletproof.
Last thing- I've completely switched to the M12 stuff for power tools and have them in a separate bag as well. If I need to drill in masonry or something heavy, I go corded.
Good luck!