We use color electrical tape just behind the connector to indicate length. We don't use NL2 at all, but the companies that I have worked with will either use the green connectors or use a special color wrapped around the connector itself rather than on the cable.
My problem with Etape is that every few months it starts peeling back and you have a mess of gooey crap all over the cable which is a huge pet peeve of mine. Zipties will destroy anyone's hands while wrapping it, and all of our heatshrink has eventually come loose. I've seen some companies painting the XLR connectors but that eventually fades off as well. I think the best is maybe colored tape or labels with clear heatshrink over it.
For multiple looms, I usually just take 1/2" spike tape and do one, two, or 3 strips at each end of the cable to differentiate the lines, and it comes off at the end of the show. I do have 2 sets of 3x NL8 which are perma labeled with heatshrink and colored tape, marked for TOP/MID/BTM zones.
