My first Easter with an allergy child as well. I have sourced rice milk (no nut, soy, dairy or egg) easter chocolates from my local absolutely gluten free shop. So I will put an egg in a bulldogs mug for him.
A friend got me onto those plastic eggs, they look fantastic! I will fill them up with his rice chocolate eggs as they don't come wrapped.
Otherwise, you could get egg dying/decorating kits.
My Mum used to always give us Pj's at Easter, or some slippers