No real food rules here. We eat a variety of everything.
I dont eat seafood (allergic) but DH will grill fish for himself and the girls occasionally and they have prawns at bbq's etc.
I dont force DD1 to eat everything on her plate but i do suggest she finishes if i suspect she isnt full by telling her its fine that she's had enough but there will be nothing else for her later. Usually she will then finish so she can have a 'treat' (jelly, fruit n custard etc)