There's one thing all my first drafts have in common: they're lacking in descriptions.
I don't do it on purpose. In first drafts I just write on. I try to stick to the plan and jump from one scene to another. Unless I'm feeling inspired, I don't stop for the descriptions. Or, well, I give the basic hints of what the place is like and jump as quickly to the dialogue.
I doubt overdescription will ever be a problem for me. Or at least, not a recurring one. Whenever I linger too long on describing something - even something important - I get the feeling the story isn't moving onward. My brain goes "ACTION PLEASE". Thus I'd be surprised if description was to bog down my pace.
While it's good to leave some room to the reader's imagination, description remains an essential part of storytelling, especially in fantasy. You can establish a mood with it. You can give a better idea of what world these characters live in. Skillful description establishes the setting. I don't want to miss on that!
The truth is that I don't think I need a lot of description to get my points across. I need meaningful details. I think it's fine not to describe a lot, if the time you spend doing it makes your setting unique. Underdescribing can lead to generic scenes. It's always better when you have an original location for your scene.
I guess the morale is not to do what I am doing. Don't be lazy with the description. Seek the specific. Seek the unique. Make the setting come to life.
Me? I'm just waiting for edits to fix it up. For now, I'm moving onward with the story!