Well, Watson Lake is an intersection of highways with gas, food and lodging. Neat historical airport with an interesting story and history. The Boreal Centre (I think there is that name - domed building near & across from the Sign Post Forest) is very neat. Some really nice folks in town - was stuck there for a couple days about 6 weeks ago (at -32*C).
The commercial camp site in town is OK. Nice showers etc. The Territorial campsite about 5 miles north of town (turn off the Alaska Highway and follow the dirt road access for a couple of km) is really nice. It is on Watson Lake (the lake) opposite the airport. Decent sized lake. I have not fished it, but I want to. From memory, two sections in the campground with around 70 or so sites.
It is not a tourist destination in my mind. it is a place to top up gas/food/conversation/- on the way through to Whitehorse, Simpson Lake, Nehanni Range etc. Some nice campgrounds on the Campbell Highway and a great loop drive around to Carmacks and then north to Dawson and over to Eagle, AK or south to Whitehorse. Or turn off to Ross River and head take the ferry across the river and explore the North Canol Road. Do it slow
You can make into or almost to the NWT if you have the vehicle. That road is not maintained. Last time on it was 5 years ago and the pot holes seemed to be breeding. The road to Nehanni is also pretty kool.
Don't forget to stop at Liard Hot Springs an hour or so drive south of Watson. Look for the fish around the boardwalk. Seems bizarre to me - small fish surviving in very warm water while it gets very cold in winter. Nice government camp site there too. Walk to the springs from your site - and then sleep like a baby afterwards.
I am not trying to knock Watson. I just think of it as a stop on the way somewhere.
My 2c
Greg