venue for big group 5/20
Yea, those aren't bad choices. Congee has room downstairs that you could take up the dining room for as Pan suggested and their price points are pretty reasonable. Congee village may be harder for such a bigger group but not a bad choice either. As for Korean food, go to Ktown on 32nd street and most of the bigger restaurants could handle your party but it is mostly Korean BBQ and you can also order some dishes to share but I prefer the BBQ
You could try calling Oriental Garden. Based on my experience, I believe a manager would work with you to design a menu that would keep to your price point. (You could select the menu in advance, but I've actually worked it out with them on the spot, and it's been fine.) I think 30 people would take up 3 tables.
If you want a private room, try calling Congee Village and seeing what they have available. Oriental Garden is better, but it's very possible to have a good to very good meal at Congee Village, depending on what you like and what you order.
The unrelated Congee has a downstairs room that is not private but isn't their main dining room, and that might be available. The food there is also quite alright.
I've had successful, tasty banquets at all three of those restaurants.
Good Korean would be very difficult at that price point, I believe, though I stand to be corrected.