I made a trifle with almond sponge, sugar free jelly in three flavours, the lime one was mixed with greek yoghurt and frothed up, a low carb mixture of frozen berries, real custard, cream and silver sugar balls.
One of the people attending as a guest was type one diabetic, so I told his partner that the trifle was low carb, and put a card with 'low carb' on it beside the dish, but by the time he was convinced he did not need to be cautious - it was all gone.
I find the frozen fruit is really useful for a quick set when using gelatine. These days I make up a teaspoon of gelatine for just one portion and don't use the jellies as they are overly sweet.
I find that the usual sugar laden or over sweetened recipes are pretty foul just because I no longer want that much sweetness in foods, so you might need to test various recipes to see what suits anyone used to low carb foods.