I agree with everything you said. The Ducks are a better team this season in spite of those issues. If they can actually find a true top 4 RHD that can play defense, everyone stays healthy, and they replace Newell Brown with pretty much anyone else, then I think next season will be significantly more competitive.
They've been better in the sense that they're not bleeding 40+ shots a night like last season and sure, the injuries hurt, but I think there's bigger problems than a lack of a right handed d and a better powerplay coach.
Some games, it looks like the team has it in them to play well enough to at least compete with their opponents. Others, like the Montreal game you see the team struggle with basic fundamentals they should have down pat through practice, the team rarely outskates their opponents and loses a lot of positional battles which results in breakdowns to defensive structure and yeah, as much as the refs call uneven games against the Ducks, a lot of the penalties are stemming from lost battles and an inability to get to optimal position. In the offensive zone the team is fine at zone entries but if it's not an odd man rush, the team really struggles at offensive set plays once their opponents get their D set up and it's not like we scorch barns on odd man rushes to begin with.
I feel like a share of this is coming from the players but plenty is coming from the coaching/game prep. This team struggles with fundamentals that we should see improving in a development year, not regressing to the same old shit. The injury issue, powerplay coach, and lack of an RHD can only cover so many of the multitudes of flaws this team still has. My hope with a new coach was that we'd see improvements to these areas even if very gradual, and the only real improvement I've seen is the team has improved at shot suppression.
The team is still bottom 5 in goals scored, top 5 in goals allowed, top 5 in shots against per game, and have the 8th worst penalty kill in the league. Ironically, as much as it would help to replace Brown, the Ducks aren't even bottom ten in the league in powerplay percentage (they're 21st). You can fix all the things you mentioned in your post and the team would still have a laundry list of issues. Maybe a healthy roster would help with that but from where I'm sitting, this either isn't a well coached group or something is rotten with the locker room culture.