A huge reason I hate the LFG tool is it prevents me from logging out and still finding a group.
In vanilla WoW, we used the global LFG channel instead of a tool. The global LFG channel was a MASSIVE improvement in quality of life because it meant I could log off entirely, logon to an alt, and level in Hinterlands or something while STILL being able to check for groups that my main wanted to join. It was like multitasking. I could go out and do things, play with others, help others, AND progress on my main at the same time.
With the advent of the LFG tool, that got stripped away. Now I was forced to stay logged on to my main. People migrated to the trade chat when global LFG was shut down, which was only broadcast in cities. So instead of people able to do all kinds of fun social things, I'm stuck sitting in town on my main bored out of my mind. And then with garrisons you don't even see people when you are standing around waiting.
Its just an awful anti-social experience. I'd like to find an MMO without a group tool. The global LFG channel was hot balls.
At the VERY least, I've been BEGGING for YEARS for Blizz to allow you to stay queued in the LFG even when you switch toons. THAT would be a massive quality of life improvement. But if you switch toons, you cannot see the queue for the other toon.