... By basically every metric, Myers outperformed Soucy defensively ...
FWIW, right now I'm happier with our depth chart's 3rd RHD (Desharnais) by quite a bit over our depth chart's 3rd LHD (Forbort) and with our highest ranked defensive prospect also being a right hand shooter, I see more of a need on the left side, which aligns with your conclusion.
I'd be interested in seeing those metrics your refer too, though. I went looking at hockey-reference.com, which probably isn't the best site for advanced stats but it is quick and easy to use. I found the following stats at 5 on 5.
Myers: Corsi Against/60 59.5 Fenwick Against/60 42.5
Soucy: Corsi Against/60 57.9 Fenwick Against/60 40.6
In total expected goals against Soucy was at 19.3, Myers at 50.2. I didn't see a way to restrict this metric to 5 on 5 play.
Now, there are obvious problems with the stats. Myers' much higher expected goals against is largely because he is a much higher event player or played with much higher event players. His expected goals for was also much, much higher than Soucy's. Also, none of those figures adjust for deployment. Myers at 5 on 5 started in the defensive zone a little higher percentage of the time than Soucy did last season, so one would expect Myers' defensive stats to be a little worse.
None of this shows who is better, but in view of the fact these don't show Myers ahead the way the metrics you refer to apparently did, I'd be interested in seeing those stats, so could you refer me to them? Thanks in advance.