I've tried everything and always come back to splenda, i prefer it, xylitol tastes like soap to me, coconut flour is extremely absorbent so you need to use lots of eggs when using it (which is fine) almond flour is great imo if you buy it from asian shops you get big bags of it and its a lot cheaper
chocolate is all good to me lol it dosent seem to matter which brand and the darker the better so i tend to go for 85 or 90% plus no one else likes it so they don't eat it hehe
if he recipe requires liquid sweetener just dissolve the splenda in a little water, someone recently told me to do that and i had to slap my forehead after spending hours looking in shops for it