I would argue that Dunfield is better overall than JDG in the middle. We never saw the best out of JDG and he was best gone from the club. Dunfield, since Mariner's arrival, has justified his first choice CM place in the team. We still have Stinson, Cordon, and Maund as backup to CM. So really we've only lost JDG (I don't think that's much of a loss, and getting the burden of his DP and wages off the books was more essential than having him as backup to CM IMO).
We STILL have Silva and Avila as AM options, nothing has changed there. Add into that Johnson who can play either wing (which is where I think he's more effective) or AM/second striker. So I think we still have depth at AM/CM overall. Avila can play either wing (IMO) and Silva CAN play wide, although he is better in the middle as we have recently all found out!
Avila is an interesting one - he was omnipresent under Mariner until recently. But then again, would any of us be playing him before Lambe and Silva, who are both playing VERY well recently? Given Avila's form before we was dropped, I would definitely be playing Silva-Frings-Dunfield-Lambe over Avila at the moment. So, again no loss at the moment, and Avila is still very good backup to anywhere accross the midfield. I'm sure if Lambe, Silva, or Dunfield dropped in form, Avila would be the first choice to come back into the starting 11.
Wiedeman had played forward, wing AND full back for Dallas, so he's clearly an adaptable player. He said himself that he "prefers striker, but will play anywhere". I think that's the appeal of the kid. Amarikwa is similar - he's played wing far more than striker in the MLS so far. So he can clearly play a couple of positions too.
So where we are maybe slightly weaker in depth on the wing (without Plata and Soolsma) we are MUCH stronger in depth in attack. And where we are "very slightly weaker" in CM (JDG) we then have a massive burden off our backs in his DP slot.
I think most of us agreed that our big depth weakness earlier this season was in attack, and we now have that depth. Something HAD to be sacrificed (that's how the MLS works unfortunately!) and that was JDG and the "luxury" players of Soolsma and Plata. I think that's a fair trade off, and we are better off now than before. Just IMO, of course!