I’d think you’ll have to lower your expectations on an unretained Allen at 4 mill. The comps don’t justify it (and in fact the closest comps are the Murray and Mrazek cap dumps)

no.

The two worst trade proposals in Montreal threads currently are Anderson and Barron.

Anderson can't be moved for value right now and Montreal should be okay with that. They don't need to move him.
Barron is still a highlight in a relatively weak pool of RHD. His development is progressing at an acceptable rate. He should have a spot on the blue line and continue to develop until someone pushes him out from below.

The second worst type of proposals are Montreal acquiring any defense period or high caliber talent over the age of 27(ish). They aren't in the position to need a Letang. That's a move for a contender. We have more defense than we need already.
Montreal needs a young top 6 winger and that's pretty much it for now.
They are at least a couple years from being "buyers" or adding rentals otherwise. Anyone over 30 will be wasting 2-3 of their remaining effective years before we can truly make good use of them. Paying assets to have someone ride out a rebuild to maybe get a couple playoff rounds before they retire or go back to free agency just doesn't make sense.

itll cost you more than 2nd to dump to bad contracts that AZ doesnt want. send them to chicago

I think everything you said in your comments is exactly how Montreal needs to approach the rebuild. Kent Hughes has said they won’t rush the rebuild. Adding players over 27 years old or so (or older) by giving up future assets does not fit the rebuild strategy at all.
Plus the Habs already have enough veterans that won’t likely be moved (Gallagher, Matheson, Anderson) that can be mentors to the young players.
People jump on Barron for the turnovers, but he is still young enough to improve on that and still provide excellent offence from the back end.