Guess that all depends on you bud. If a guy tries to fit his entire truck in there, needs to get the vice grips out to pull the zipper closed, then yeah, probably a hassle to lug into attics. For me, I've found I really don't need every tool I own on every job every time.
The MB I have set up as a Diagnostic Kit, this is all I take to the roof. I tote a meter, amp clamp, temp probe, jumper wire, channel locks, wire strippers, allen wrench set, small adjustable, 1/2, 9/16/, & 5/8 wrenches. And my Digi-Cools.
By the time I'm reaching for my LC, I already know what tools I need for the job, so my LC Inventory tends to change with each gig. Here's an example: I do a fair bit of my day on supermarket rack refrigeration, so there is a handheld telephone in my LC for when I need to verify EMS Dial-Up info. Not sure I'd EVER need that up on a rooftop AC or in an attic. I don't take everything to every gig.