@fiercelv If I may try to help:
"GIVE ME AN ENGINEER" (or other) text markers have color on top of them, showing who made them. So you know who want engie etc.
"Rampant, unpunished lagers. REHOST 24/7 Self explanatory." And "Lobby Kicks" / "CPU Snobs". Those are two sides of the same problem. Might want to learn how to use f11 ingame, to determine who is lagging, or is it you. And what type of maps and player count your computer can handle. Smaller maps and less players and smaller unit limit of course are easyer on CPU. If necessary you can pick smaller maps, and also tell in lobby, that you have played/ you know you can handle this type of map. Lieing of course can make joining later much harder.
Also you can ask joining lobby, if your score is a problem. Some players/ greys too ask that.
You can host your own games.
And you can choose games you join. If host is bad, as you described. Remember him and dont join any more. And if host is good, remember him and join his games. Same applys to accepting toxic players in your own games. This can be quite effective way. Especially if lots of people would acknowledge theyr impact on game. I have seen bad hosts later wait for hours and never getting game full.
Best wishes