I think a commish should try to make it the best league possible -- i.e. high level of competition, good owner pool, no abandoned teams, no teams with massive pitching fatigue, making the blog informative -- to give owners incentive to stay long-term.
This was the first time, in 12 seasons in the league and I think eight as commish, that I have sitemailed owners asking them to consider vetoing a deal. It was an exceptionally bad trade, and I wanted to make sure owners looked at it closely.
Similarly, if an owner has massive pitching fatigue, I send a trade chat. If an owner shows up sporadically I sitemail to find out what's going on, and on more than one occasion, the owner has real-life issue causing problems, and volunteers to relinquish the team. If a team is on the verge of abandonment (a rarity), I line up a potential replacement.
I don't think any of this is bad.