This might be the lamest "enhancement" but it helped me out.
I got home from work today with a systainer 4 packed with drill bit sets, it was heavy.
I also had my dog with me, and from experience carrying a systainer and walking her
is not a fun experience. The systainer invariably bangs against my leg.
I should mention I don't have a driveway, so I park on the street. Tonight I had two blocks to
walk with the systainer and the dog.
I looked at the T-lock handle and an extra dog leash I had in the car.
I thought if I could thread the leash through the handle it would make a handy strap.
The leash was thin enough and it made it through the handle. This will only work with the
thinner leashes, I think it's 3/4".
I can't say having the leash dig into my shoulder was comfortable, but it was a lot better than
holding the handle. If you used a strap with padding I'm sure it would make carrying a heavy systainer
a bit easier