First Brisket (What did I do Wrong?)

I want to learn from my mistakes and any advice is appreciated. The brisket was drier than I wanted it to be.

I used a Smokey Weber Mountain and maintained external heat around 250°F. I wrapped the brisket at around an internal temp of ~170°F (around 5 hours in) with aluminum foil. The brisket reached an internally temperature of around 208°F (at about 8hrs in to the smoke) And I pulled it out and let it rest for 3 hours in a cooler.

• No major bark was formed (I'm thinking I didn't use too much rub to help form the bark. I only used one tablespoon of salt, and one tablespoon of crushed pepper).

-Would the bark formation help retain more of the moisture?

-Should i have pulled it out at a lower temp?