Yes, the Baneshwor Banquet I was referring to is located just before the downhill starts when you head towards Anamnagar from New Baneshwor Chowk. US_returnee also mentioned one of the other very important factors when you organize a wedding party, you want to make sure that your guests will have no problem getting taxis after the party. For that Baneshwor Banquet is located very well. I had one of my friends who was so drunk that he had to leave his car in the party palace. The party palace had a party next day in the afternoon. But still, the staffs were very nice and they had absolutely no problem leaving the car in their parking lot. My friend went back 3 days later to pick it up. This is when I was pleasantly surprised by their customer service.
They also have a guard. May be you can ask the guard to check that your guests have invitation card to sort out the free loaders.

I have seen many party palaces in Kathmandu but many of them are located in areas where it is very hard to find taxis when it starts to get dark. At the same time it is normal. A good party palace requires a big space and it is hard to find big spaces close to center of kathmandu these days. So yes, Baneshwor Banquet is not bad at all in many aspects.