Hi and welcome cobble86, it's really a hard one when there is allergies and foods that they don't like involved. I can understand you wanting to make an impression. What about some chicken Kiev, it's nice a simple and I can feed all 7 of us with some left over using 4 chicken breasts. Served with either veggies or a salad goes really well. And maybe a yummy self saucing pudding or an apple crumble with some TM custard.
I don't know the choices are endless. Good luck with finding something to suit everyone.