If you have time and can stand the cold - depending on season - spend some time, a day or two to explore the other lakes around Gosainkunda. The best map to use for such exploration is the Finnida series in 1:50.000.
There are a couple of interesting places on the trail toward Rasuwa Gardi, the border to Kyriong, Tibet. Kyriong, incidentally, is the place where Peter Aufschnaiter and Heinrich Harrer stayed a few months in hiding - more or less - waiting for clearance to get on toward Lhasa ("7 Years in Tibet").
The border is closed from the Nepalese side, with a fairly big Nepal Army garrison protecting the border. Locals can cross. On the Tibet side there is a good road.
If you turn east before reaching the border post, and up, sort of toward the Langtang Ri "lekh" you will reach a couple of fairly small Langtangpa villages who are doing well as fruit growers. Above the uppoermost villages - you will have to ask for directions - there is a trail continuing to a lake which is another of these Dudh Kundas, a locally holy lake colored turqouise from glacial debris. I never went there, but a local is telling this and tempts me into going - soon!
Most people just hurry over the Laurebina La pass, and it gives sense when staying overnight up here is not part of the plan. But if there is an open hut down at Gosainkunda Lake, or with a tent, this is a good place to explore further and stay a few days.
Up at the water divide near the pass itself there are a few nice peaks that can be scaled - with care and necesary equipment (snow, ice, cold). I can imagine there is a fair avalance danger here under the right (wrong??) conditions, and it's not a place to get hurt and incapacitated. Nobody will find you. Not an undertaking on your own, in my modest opinion.
On the photo, Laurebina La itself is just above the little lake.
Gosainkunda lekh is the ridge and chain of partly snow-clad mountains that partly obsucres Langtang Lirung Peak seen from Kathmandu. A perfect place for rambling around - when geared up for it.
Off-season there is no overnight possibility in the Gosainkund area, and you must either cross over to Helambu, return to Singh Gomba or camp out.
The latter possibility is a splendid solution to exploring this area. There are many smaller peaks in this area, and lots of more lakes and places to see. There is a good supply of drinking water and plenty of places to put up a tent.