You do realize that the removal of teamwork in lobby with new champion select and the mish mash number of players allowed in a premade actually decrease teamwork and team play significantly? Don't you?
The game is less team oriented now than ever before, partially because of the new lobby, partially because of dynamic queue and the tendency for people to only work with thier playgroup in game instead of doing what's best for the whole team.
There had never been anything more counter productive to team play and a team oriented style of participation in game and pre game than dynamic queue and the new lobby. This is why a large portion of the high ranked population, if not our entire population in high Elo, truly dislike the changes. We already worked like proper teammates before this, we automatically tried (in probably 90% of matches) to put each player on optimal roles and champions after using op.gg to figure out an ideal team comp. Forcing a particular role on players, regardless of pick order (picking mid lane first in high diamond is a great way to get auto countered and lose the game in lobby) actually reduces teamwork. The system is no longer flexible enough to allow the teams to do what we all know is best for the team.
There is no portion of the changes since December that reinforces team play or team focus. Every change since then, every single one, has decreased the value of, and the likelihood of encountering, team play in game.