I like
Clarity the best. It has a nice sound.
I don't think
Destiny came into use until the 20th century; at least I haven't seen it in any lists of Puritan names. It has a nice sound, but I don't really believe in any sort of destiny, so it doesn't sit well with me.
Serenity, as much as I want to like it, it just reminds me of adult undergarments. You could use the nn Seri or
Sera, I guess.