Pretty good rundown here about what makes this 3-3-3-1 work. At the end they start talking about Toronto. I think we can take Toronto and the Kemar/Adams wingback is as elite as anything in MLS. My worry more is the Jozy v Long situation, as Long ahs not been up to the task against elite forwards. Secondly, set pieces. Traditionally under Marsch we've been very strong at defending them, but this year we've been horrible. If that back three somehow holds up, we'll be in good shape.
I've been saying this a lot, but this 3-3-3-1 in the midfield does not work without the yeoman's work from Davis. The dude just is the glue that makes it work in the center of the field and connects the back to the front. He's been amazing. He started off the season very poor, but his game improves week by week.