It sounds to me like you expected managing remotely to be exactly the same as managing locally. You expected to be able to gauge the morale of the team, to know what people though of the groups future, etc without having to actually DO anything. When working with people locally, you at least get the impression that you understand these things from general interactions. You are wrong, of course, as your intuition is just as terrible as everyone elses, but you at least get the feeling that you know the situation.

Of course managing remotely is different from managing locally. Coding, and actually being a productive knowledge worker, however, really isn't. Luckily, managers already make a large multiple more than most others in the organization, so asking them to adapt and work harder to accomplish their responsibilities should be less of a big deal than dumping that kind of thing on lower level employees who area already generating far more value for the company than they're being paid for.

edit: Oh, and brainstorming is a terrible waste of everyones time and is worse than a total lack of it. Multiple studies have been done and show that brainstorming results in groups taking far worse actions than if they use other methods of coming up with solutions.