Crock Pot Fiasco (sort of)

Last week I tried cooking a pork roast in a slow cooker, along with a mix of sweet potatoes, carrots, leeks, and a cup of broth. There are also these other potatoes I thought would be sweets, but looked like regular spuds on the inside.

I put everything in the crockpot as shown in the "before" picture above, but I think I did something wrong. After 4 hours, the pork was fully cooked, but dried out like I cooked it in the microwave.

I was able to salvage it by slicing it down and mixing in with the cooked broth and veggies. It was absolutely delicious, but it looked like an unappetizing mush. You should have seen how my wife's face transformed from excitement to scorn when she finally saw what smelled so good. Sorry I didn't take an "after" picture.

1. So what did I do wrong?
2. Was the pork sitting too high atop the vegetables?
   
3. Should the pork have touched the bottom so it could cook partially immersed in the broth?
   

I'll try that next time, but I'd appreciate any advice.

P.S. - Leeks are my favorite new ingredient. They add a lot of tart, bitter flavor. I like to chop up the whole leek, using as much as possible down to the bottom of the stalk until it's totally white.

Leeks are also, by far, the best vegetable for drumming up and down the produce aisle when you're pretty sure no one is watching. They're like big brushes, perfect for Mitch Mitchell's solo at the beginning of "Up From the Skies."