There's no way the L700 is better than the 007, at least in my experience. The L700 sounds more artificial and "off" at least in terms of midrange tone, whereas the 007 sounds more natural and is better in nearly every technical aspect. The issue with the 007 is that it's one of the least user-friendly headphones out there, hard to amp, very fit dependent, self-adjusting headband system that's awkward and keeps pulling the headphones out of position, modding required for the Mk2 models, etc etc. The 007 has the potential to sound really bad in the wrong system whereas the L700 generally sounds similar from system to system. But the 007 will scale and leave the L700 well behind. In regards to the 007 being too dark or too laid-back - just EQ 2-6khz up a little bit and problem solved. You need an amp with plenty of headroom though.
There are reasons to fix the L700 Mk1. My broken yoke on one side is one. It's a good thing the new ones are metal. Also, the earcups have little tabs on them that prevent the top of the earcup from swiveling outwards far enough, putting too much pressure on the top of the earpad, and not enough on the bottom. It's an asinine design, and I'm guessing the extra bend in the yokes in the Mk2 is there for that reason. It would have been smarter still to delete the tabs entirely.
Granted, the L700 is still rather good. Very punchy and dynamic, with a very 3D and holographic stage. The latter is probably the best aspect of it, that and the general forwardness of the presentation. But the 007 it ain't.
RE: ES1a - interesting, and I'll put it on my radar. Maybe if impressions keep being positive (and I want to see some more comparative measurements) I might pick one up later down the line. Lots of other things to get to first.