Well I'm not sure what the ideal advisor is, but in my experience advisors can be categorized into two broad categories:
1) The Overmanage-r - This advisor is probably young, ambitious and childless. He is great because he is up to date on every important paper and every concept, so he can work side-by-side with you and his other students, just like he did not long ago in grad school. His downside is that he works insane hours and expects the same from you. He wants to publish early and publish often and if you can keep up and not lose your mind (which you just might) you'll probably graduate with an amazing CV.
2) The Undermange-r - This advisor is older, established and busy with family and administrative obligations. He is great because he isn't breathing down your neck, doesn't mind if you don't show up at school for days and gives you the space to discover your real passion within the field. His downside is that he never pushes you towards anything and can be hard to track down. He believes that getting a PhD is about learning how to manage yourself with little intervention and, if you get yourself through your dissertation (which you may never do), you will have done it on a topic you're passionate about and have developed all of the necessary skills and personal motivators to be a great researcher yourself.
There are obviously more than 2 categories of advisors. Categories I often hear about are:
"the Jerk" - Self explanatory, but mostly just a sad personality trait
"the Unpredictable Jerk" - Also self explanatory, and usually a combination of the over- and under- manager, someone who is never around and then shows up and wants you to show them the world
"the Really Big Jerk"...etc.
There are probably also advisors that fall in between these two, but when I hear about them it's usually "As he's getting older he's less intense" or "He used to be great and now he seems to be losing interest". But overall, all advisors that I've heard about tend to exhibit one of these two managerial habits more than the other.
So today I was trying to imagine what the perfect advisor would be, and I don't think I can really say. Personally I think that an Overmanage-r is better for me. My main advisor is an Undermanage-r and I really like and respect him. I appreciate that he never pushed me towards a topic of his own agenda and I've seen self-motivated people flourish under his (light) direction. But recently, when I began working with an Overmanage-r I think everything came together for me.
Like hitting rock bottom, I fell into a deep PhD Depression when I first began working with this Overmanage-r because I felt overwhelmed and unable to start what I saw lying ahead. But thanks to the micro-managing and side-by-side work, I have begun to progress in my dissertation at a rate that I never thought possible after many years of no progress at all.
So without my Undermanage-r I wouldn't have had the time to explore various topics (and land on a topic with his help) and without my Overmanage-r I doubt I would have ever gotten the nerve to start down the path. I'm not out of my PhD depression yet. I have lots of concerns like if I'll be able to keep up the pace I've started (maybe, if only for a year...) and if I could do this on my own if I moved into my own research position (probably not...but only time and progress will tell...), and I still have bad days where I feel like I was never smart enough to be here in the first place.
But for those of you in the middle of a bad period, let me give you a little bit of hope from almost the other side (for today) - if you ever enjoyed the subject at all you will probably come out of this low (that's why it's PhD Depression and not real Depression). If you're back in a low after you thought you escaped, that happens too and is ok too. The question is: When is too much unhappiness too much? That is a long answer that I am trying to answer for myself and all of you here.
For now I want to know what your advisor is like...
We can't get a detailed answer there though, so after the survey go leave a comment about what your perfect advisor would be like...
Maybe it's one of these* =)
*Thanks to Charlie, a reader that suggested I check out the funny but sadly no longer published Dent Cartoons