1**.** I just counted most of my ranked games (For convenience sake I skipped most champions with 5 or less games then added 50 games per season, so I don't know the precise value) which was over 2000 games, then counted all games with support champions (Minus those I know for a fact weren't "support bot lane" games, like those 12 Sona games in Season 5, which were actually mid games. I added +5 games for those full-retard, but not troll games, like support Rengar) which ended up being around 40 games.
40/2000=0.02=2% +/- 0.5% of support games over 3 seasons.
Hm. Now that I think of it, I should've included Season 6 too, since it allowed you to dodge autofill at no penalty.
Or maybe I did count it... now I'm lost.
Ah, right. What promted me to count my support games, was the guy saying that with pre-Season 6 Pick Order you must've been able to support more often than with Role Selection of Season 6 and 7, so I didn't include Season 6, which is relevant to the autofill issue as I mentioned above.
In season 6 I played exactly 3 support games and easily over 300 non-support games. That's less than 1%.
If you want an actual source, I cannot provide it here due to Boards mods being anal about it.
I can however send it to you, if you have, say, a Reddit or Google account - assuming you can message people in Google.
Never had any incentive to see if you can.
2**.** It does not indicate somebody wrote something in the lobby, unless they directly messaged you. No idea about the new client, though.
That's just my perception bias. On average I only get to talk with 1 person per 2 matches.
Role/champion trading is even rarer.
As for chat restrictions, it's something I noticed in 2014 some time after that garbage was released (technically speaking it was a complete shit of a system).
People were talking less and less with each other. Not even only trolling. All kinds of chat
3**.** And Solo Queue wouldn't be brought back after a year if it was working.
Riot isn't willing to share that information unless it's an accomplished fact and they already acted on it.
The queue times for the first game are either the same or slightly lower, that's true, but the amount of dodging caused by people getting their worst role is many times higher than what it was.
In previous seasons getting somebody to dodge was miracle to the point I made up for 90% of dodges in my games.
Now I get 2 dodges per game on average and I'm not the one dodging.
Remake the room as in, upon chosing a game mode(ranked DQ) but before starting the actual queue, you'd get a message saying if autofill is on or off.
If it was on, all you had to do was to quit the room and pick the queue again at no LP loss.