Catering Mavens: Help needed (Sushi/asian fusion menu) (grilled, tuna, shrimp)

[Amelorn]

Hello all,

I in the middle of planning a graduation party for anywhere from 20-40 people in early/mid June. From my invite list, it depends on who brings their spouses, children etc. It's also a bon voyage party for my grandparents and me, and it's at my grandparents' house. It promises to be a bash not seen for over a decade. In mid-June, we're flying to my graduation (Scotland) and also doing a Euro-trip (Germany, France, Ireland). Might as well if we're in Europe anyway.

The food menu:
This part is difficult. I am going to do an Asian fusion menu. I originally wanted to stick with just Japanese, but of the places on my list, their catering menu had far too many compromises (chicken gyoza dumplings instead of vastly more popular and traditional pork; too many unpopular vegetable "filler" rolls in the sushi platters) and the discount versus a la carte takeout was less than 10%.

I decided to use a very good Asian fusion place (ie where quality compromises are not made on the sushi or the various cooked dishes). They don't have a catering menu, but I don't care. HOWEVER, I'm really having a difficult time with portions.

Here is the menu I decided on: http://www.takuasian.com/taku.pdf

I was thinking that for 20 people
15 portions of soup (some balance between miso and wonton soup)
5 orders of gyoza dumplings (30 dumplings)
3 orders of beef negimaki (15 pieces)
Lots of Salad + that Japanese dressing

20 pieces of mixed nigiri sushi
26 rolls: 3 tuna, 3 california, 3 yellowtail, 3 spicy yellowtail, 3 spicy tuna, 3 spicy salmon, 3 spicy crab, 4 shrimp tempura.

A portion is equal to an ample dinner for one

4 x spicy mango chicken
3 x grilled sea bass
3 x Ginger glaze shrimp
3 x General Tso's Chicken

Ample Fried/White/Brown rice

Any thoughts? The reason that the sushi rolls are so ample is because they're favoured by the younger generation. Hell, if I'm hungry, I can eat 5 of them! If I'm going closer to 30 or 40, how do you suggest I go? Increase amounts of what I have, or add more variety?