Gonna need more info, but for starters I would recommend getting your temps up by 25° at the very least. I usually cook in the 275° range but that's how my rig works best. Brisket is a long cook regardless but it is going to take significantly longer at a temp that low. I also always run a water pan, but it isn't required for a high quality product.
I'm in the camp of bump that heat up to 275F smoker temp. Briskets do not care one bit what temp they are cooked at as long as they aren't being burnt. So crank it up or be prepared for a 24hr smoke hahaha.
The MES doesn't like to burn chips unless you are at 225F smoker temp or higher and the temp readings from the MES smoker thermometer and meat thermometer are ALWAYS off so keep that in mind. If you have other thermometers to use to check smoker temp and one for meat temp that would greatly help you out.
Finally, and I can't stress this enough.
Your brisket will only be done when you can stab all over with a kabob skewer (or your temp probe) and it goes in like butter ALL OVER.
Briskets are NEVER done by time or temp, ONLY by tenderness.
Put your meat temp probe into the thickest yet center most portion of the Flat muscle.
When it reports 200F Internal Temp (IT) of the meat then stab all over to see if it is tender.
If you have any resistance anywhere then let the temp IT of the meat raise another 2 degrees and check for tenderness again. Repeat until it is tender!!!!
The #1 reason people fail on brisket is because they bull the brisket out too early because their time estimation was off.
I imagine you are going to run into time estimation problems having started at a 200F smoker temp so plan for it to NOT be done when you expect it to be done lol.
At a 275F steady smoker temp and not opening and running unwrapped the whole time a brisket takes a little over 1hr per pound before it becomes tender for me. So your 11 pound brisket at 275F, unwrapped the whole time, in my smoker would take about 12 hours usually before it is tender and done.
At 200-225F smoker temp I would imagine you are in for more of a 24hr smoke or longer before it becomes tender and done.
So just be aware that it will likely not be done when you initially imagined and just roll with it. The brisket dictates when it is done. You can influence it with temps and wrapping etc. but I feel you are likely at the mercy of the meat now :)
Oh, I add no water in an MES and vent 100% open the whole time.
I hope this info helps, and just hang in there and expect this to be a major learning experience :)