I have gone to 3 of the four years this festival has operated, and I enjoyed all of them. It brings so many different types of music to an urban area not many had gone to before, but over the years people have begun to flock to again. LIB has helped in changing the image of downtown to a more friendly and relevant part of the city. And yes from year to year things change, displays, areas you could go to one year but can't the next sucks. But hey life is still beautiful.
The festival itself takes up 18 blocks of hotel and some residential areas. There is so much to do, and see that I couldn't possible name everyone I've seen. Favorites: kings of leon, the killers, stevie wonder, just so many.
There are food options, but like most festivals it is just really expensive and anything really good tends to run out. So, I recommend travel out of the festival to get your grub on.
Parking... this can be an issue. I find that uber/lyft works best if you aren't staying in the area. Otherwise $20 bucks to park at any of the available spots will hurt the wallet/consumption of drinks.