This a weird trade for me to assess. Given Husso's extension in January, it seemed like the writing was on the wall. But, Binnington's play over the course of the full season wasn't very inspiring. I thought maybe, with how things played out towards seasons end, and how good Allen was might entice management to hold onto him. Obviously, you don't hold onto your backup goalie when your in dire need of cap space and he's expendable without taking money back. But, I do think the Blues may end up missing Allen more than people think. I found a nice article that summarizes a lot of my thoughts.
A Full Assessment of the St. Louis Blues Jake Allen Trade
Now, the Blues sit with slightly under $6.4M in cap space now. So obviously, another move is forthcoming.
As for my opinion on Allen. He clearly was never truly capable of carrying the full load of an undisputed #1 goalie. But, he was always a strong backup/platoon goalie. The Blues are putting all their chips on Binnington, because it remains to be seen how Husso handles an NHL net. So only time will tell if the bet pays off.