3300 CP 14 15 13 93% Smack Down Stone Edge Tyranitar Power up?

Go for it. I power up pokemon with IVs 90+ but that's just my personal preference some people power up pokemon 82+.

Let me preface this by saying no matter what, DO NOT TM OFF SMACK DOWN
Its hard to answer this question without more information. How are you on the side of dark/ghost types?
If you dont have a good number of them, i'd say look for tyrantiar raids. They're both a good place to get good iv double dark tyranitar as well as more candy. Its dark set is more useful at the current moment and will be for a while.

For right now, there isnt much for a double rock set pokemon aside from alolan marrowak until we see how the PvP meta breaks down.

I would reccomend you to not max anything unless you're lacking generalist such a Mewtwo, Rayquaza, Metagross or so... If you're trying to get good damage on a legendary or tier 4 raid then evaluate the best counters you have and get them to their breakpoints... Tyranitar SD/SE is more of a specialist... What I do with my best specialists is I take them to lvl 25/30 and if a I need them for a raid I see if I can afford taking them to the next breakpoint

Well it is your first tyranitar and I also bet it's your best rock attacker. We just had the event with exclusive move returning, so there are no reasons to stock up in candy.

On the other hand, it's already over 30 levels so it's very usable right now without further powering up and since it's your first (and tyranitar is also a dark attacker) it is wise to save up at least 125 candies for your next larvitar hatch to build a dark attacker.

Right now rock is just a supreme counter for scyther, which is an easy boss. If you are asking mostly for raiding, the wisest choice would be to wait till new bosses appear (or old ones return). There are a few psychic legendaries in Gen IV that will be countered by a dark Tyranitar, so it would really suck if you don't have enough candies to evolve and power up one. The rock Tyranitar is a great counter if the birds return. I'd say saving your candies for a little while is probably the safest option.

Anyway, even if you decide to power it up now, wait at least till we see the cost for adding a second move. It will be any moment now (update is now rolled out for both android and crapple)

No. There's currently no need for a maxed rock Ttar and from a raid perspective it would be much more useful to spend the rest of your candy on making a dark Ttar or two.
PvP may be a reason to max it though, we'll see about that in just a day or two.

I am going to be very unhelpful and say "yes" and "no" ;)

YES:
It's a really good rock Pokemon with a move set that you won's see again in probably quite some time. You could of course trade for one with a friend and perhaps get a better one, but the one you have is already good enough to power up.

NO:
At 3300CP I guess it's already at a fairly decent level (my 3266 is lvl30, so yours is perhaps 31?) and it will cost a good amount of stardust and candies to power it up.
Will it really be that much better if you power it up?
Also, seeing as it will cost both stardust and candies to get an extra move when PvP comes out you should perhaps wait and save all stardust and candies until we know how much those moves will cost.

Personally I would lean towards "No", atleast for now. 232 candies is a good amount, but powering up at higher levels is damn expensive. And, as I said, with PvP coming you might want to save some in case you want a 2nd charge move on that Tyranitar.
I mean, we don't know if we will have to pay 10 candies or 100 candies for an extra move. Or more.

But this is coming from someone who hates spending dust, so I am not impartial on the matter of powering things up (I never power up nowadays)
;)