So the basic idea isn't half bad, but it really lacks the punch that you used to see in the Bant Hexproof decks because of the relatively low number of creatures that actually have hexproof these days. Before the appeal was to use either
Invisible Stalker, mostly for the unblockable part, or
Geist of Saint Traft, mostly for the angel tokens, and pump the crap out of them with enchantments. The real strength was that there were relatively few ways to deal with those guys before... now, well,
Celestial Flare,
Devour Flesh,
Anger of the Gods,
Supreme Verdict and a variety of other tools are available to work against you.
As a result, you have only 11 hexproof creatures, meaning you're unlikely to have more than 1-2 creatures out at any given point in time. As a result, you're likely going to get wiped out pretty hard by a single hit. In the current meta, you likely could perform alright against most decks, specifically mono-black devotion is likely weak against you, but anything that overloads
Cyclonic Rift or holds a board wipe is just going to clear you out rather easily. It's worth a shot
To the specific details of the deck, you DEFINITELY need to up
Witchstalker to 4x and could consider some other creatures in addition to potentially adding
Alpha Authority to your list of enchantments. I would say to drop the
Elvish Mystics as it's not like you're really struggling to hit a high curve, so the ramping isn't really necessary.
Aside from those changes, it looks about right, but again, I don't know how good the strategy will be these days.
Lastly, for the sideboard, I would suggest thinking about what types of decks are normally present at your local FNM. If it's a control-centric crowd, figure out the pieces that would best serve you to combat control builds and slide them in (I'm thinking
Rootborn Defenses,
Bramblecrush, and things of that nature). Alternately, if it's an aggro crowd, you'll likely want to slip in things like
Trostani, Selesnya's Voice,
Call of the Conclave, and things of that like. If it's mid-range, well, you're already pretty well suited there, but a few copies of
Sphere of Safety might be fun.