Copp would be better defensively than Haula without being an offensive upgrade. Hall and Pasta bleed chances against so its probably the best *value* option for that line in the short run, but doesn't really help longterm like a Hertl deal would.
However, if you think the Bruins need to concentrate on D more than the forward group its hard to afford Hertl, too, and not have him walk away (unless you think Bergeron is retiring which I cannot even consider without curling up in the fetal position on the floor).
Copp is not a guy that I would considering moving a 1st for in the slightest (especially with how good the Bruins first would be if they get knocked out of the first round), but perhaps something with DeBrusk and Copp being the main pieces. Or maybe a prospects driven deal concentrating on Studnicka.