Hey BW, welcome to SMF from NorCal. Glad you are here with some questions. We love to give answers, and often they make sense!
You can use the Search feature in the upper corner for "Brisket Stall" and will get a lot of answers. Try that first and you make find exactly the information you are seeking.
Now, I've seen big hunks of meat stall anywhere from the high 130's to the high 160's. The lower the smoker temp, the longer the stall.
As far as the meat being dry, a couple things. Not cooking it long enough will leave a tough cut tasting dry because the collagen hasn't melted. Cooking it too long will cause the same result because all the collagen has melted then was squeezed out of the muscle tissue. That's where the probe test comes in. Poke it with a temp probe, toothpick, ice pick, double pronged fork, etc. When it slides in like warm butter, it's done. Might happen at 185F internal temp, or not until 210F IT. Meat can be weird at times. I've had one cut (a chuck roast, neighbor to the brisket) that never got tender. Ended up making chili with it. Was GREAT chili!
Raising the smoker temp, and choosing a point to wrap the meat, is about technique. The experienced folks all have their own technique. Since you and I have the same equipment here's my technique. I dry smoke BTW; no water in the water pan, or very little (2 quarts) if I want to lay down more smoke on the meat in the beginning of the smoke. I don't use the water to control smoker temps. I used the vents until I got a blower. Now the WSM is like setting the oven because of the blower.
1. Light the smoker and watch for hints of light blue smoke. With my blower that's usually about 30-45 minutes. Up to 90 without the blower. If using water, this is when I add the boiling water to the pan, just when I'm ready to add the meat.
2. Pull the brisket out of the refrigerator, apply rub, and throw in the smoker. I'm a hot n fast guy so I'm at a smoker temp of 275-300F until I wrap it.
3. As soon as I see the internal temp of the meat at 170-180F or so, it's out of the stall and that's the IT when I double wrap the meat in HD aluminum foil with a little beef broth.
4. Crank the WSM up to 350F once wrapped until the IT is 200F, then probe it right through the foil. Remove at the butter stage and let rest for 1-3 hours in the wrapping in a cooler or on the countertop covered in old towels.
This technique works for me for both beef brisket and pork butts/shoulders.