As far as west texas goes...Alan Henry with a crowd is a death trap.
And a low amistad is right there with it. You'll have to check your pants when you see some idiot flying across the main lake is his brand new ranger but can't stay in the channel. That lake can go from 80 ft to 2 ft reaaaal quick.

White Rock Due to the scenery at times

Palestine for stumps
Lewisville for traffic
Texoma for rough water

The one they let boats on.

Well there ya go.

Lakes aren't dangerous for the most part, people who have little common sense, well that's a different story.

Welsh can be pretty dangerous. Between the fog & zero visibility in the mornings.

Then you have killer stumps & floating logs everywhere.

Lake Austin mid summer at 1pm....DEATH TRAP

+1, or Travis.

Lake Travis has long been known as one of if not the most dangerous Texas lake as far as deaths:

http://www.highlandlakes.com/laketravis/editorial.htm

Palestine

The amazing part is people actually putting their boat up on plane and running in zero visibility in the fog. I mean Really. I have a GPS that I can use for navigation too, but I cannot see the other boats in front of me. There is absolutely no way they could stop in time if they overtook another boat idling down the lake. At Welsh, I idle around the 1st point to the left and start fishing in there until the fog lifts just for that purpose. Then listen to boats run by at 50-100 yds away that I can't even see and shake my head and pray they don't kill somebody or themselves.

Experienced it myself last weekend. Wind wise, Falcon with a north wind is killer if youre on the main lake or down south. Lewisville is absolutely horrible during the summer as well with all the cabin cruisers.

Lewisville for idiots and wind. Texoma and amistad for BIG water.

I don't know if it's the most dangerous, but Livingston probably intimidated me as much as any lake. It's huge, wide open, and generates big waves in even a moderate breeze. Add in stumps everywhere and it seemed pretty dang dangerous to me.

Leaving the Pavilion or Twin Dikes at Rayburn in anything short of a small yacht in a strong NW wind seems like a suicide mission. We drove across the dam one day with a 30 mph NW wind, gusting to 45, and from the look of the waves crashing onto it you couldn't have paid me enough to try to make the run from the Pavilion to Veach. It was an awe inspiring scene.