1 - I don't think its the jobs coach to create the culture of the organization. This should be done by the owner, president of hockey ops, or the GM. The head coaching job does have a few responsibilities, like developing prospects, discipline etc, but the most important (and in reality the only job that matters) is winning hockey games. You want to fix organizational culture, its amazing how quickly winning and success fixes that.
2 - As far as the Americans wanting to stay here, I don't think that really falls on DJ. None of these young American players have signed extensions as a UFA, so its not like they've had a ton of opportunities to abandon ship even if they wanted. Plus, I think the idea that all capable USA born players only want to play in US cities with low or no taxes is overblown. There are a lot of American players who play for Canadian teams, or in US cities with high taxes.
3 - "They are tough to play against" is often the only kind words you can say about a team after you've beaten them repeatedly throughout the season. It's like the "They've got a great personality" compliment to the ugly person you'd never date but want to say something nice about. We haven't been hard to play against. Our defense structure has been non existent, we give the puck away way too easily, and our goaltending tandems have statistically been some of the worst over the last few years.
As I made in my first point, winning fixes all of these problems. If a coach is getting wins, the culture is good, people want to play here, and yes we're obviously tough to play against if we are beating the competition more than they are beating us.
When you aren't winning you gotta try and take credit for these small victories like "Hey this guy was willing to re-sign here, OMG they must love the coach!"