You can probably have a huge bowl of sugar free jelly with berries and cream or yoghurt - if you are a type 2 watching the carbs - on festive occasions a trifle with almond flour sponge softened with a little squashed fruit and maybe a splash (or more) of sherry), berries in the jelly, a lot of real custard made with cream, eggs and vanilla, whipped cream piped on top and segments of mandarin orange carefully deskinned and the zest scattered on top.
I use pure gelatine to beef up ordinary jelly as making up a jelly with artificial sweetener with only a small amount of water can make it overpowering - I have really sensitive taste and smell so it might not affect everyone, but particularly if children are likely to want to try it the gelatine is probably the way to go.