I think very few high level players can tolerate patch 1.18.
I don't think Blizzard will revert to 1.16.1 or fix most of the critical problems with 1.18 any time soon.
I think the UGL community should officially move to a server which supports 1.16.1.
This move could be temporary, if Blizzard manages to fix all the problems somehow.
I think if this isn't done, UGL and competitive FMP as we know it will die. (At least western, english speaking FMP)
From what I can tell, iccup and red-g server are going to stay on 1.16.1. (Actually I'm not even sure Red-G is still alive)
Unfortunately, red-g is full of laggy mexicans, while iccup is BW-only and full of hackers.
A third option is to host our own server. It's less desirable because there wouldn't be an influx of new players from the casual/public sector.
Option four is a server called Netcraft which is accessible if using mca64. Don't know much about it, but it works.
No matter what, this patch is going to be a huge blow to our already small population.
But it may be possible to keep this great game alive for awhile longer.