Still very early days. Poor/average first game is quite common.
Would be more concerned about defensive solidity than attacking shortcomings if I supported England. Some of the criticism of Southgate is over the top, but it's also strange to come into a tournament like this and not really know what your central midfield should look like. He may very well get the answers he needs as the tournament progresses though.
Trippier at left back as anything other than an emergency option I don't get. He can do a job, but even on the right he's vulnerable defensively. Makes up for it on the ball and with that right foot, nullify that and it's a real weakness.
Decent start for the bigger teams, but some of them against rather average at best opposition...
France, Portugal as long as they don't get stuck in Ronaldo main character syndrome, then a bunch of teams. Including England.