Help finishing my Y!Tiki BoF build please

Welcome to the game :)

It's a nice team you have there. I would consider putting triangle adept on your NY Azura; that way she'll crush the blues if you have an issue with them since you have two reds. It's not a short-term placeholder skill until she gets something better, either; she can continue a long time with this skill.

The Y.Tiki you have right now is a mixed phase unit with really nice spd. She will really put the hurt on enemy dragons, since most of them aren't fast enough to keep up with her. I agree with your choice of A-skill. Breath skills are quite nice, but fury works beautifully with Breath of Fog.

For the B-skill, renewal is a very reasonable option; if you choose that then reciprocal aid could be useful as a way to heal the team whenever Tiki isn't fighting. Vantage, I can only see being useful if you KO your opponent right there and then; otherwise you end up taking the hit anyways, and it's actually risky because you're helping them charge the special. (For example, if you ever vantage a Nephenee by mistake, you will receive a wrath moonbow which might end her in one hit.) One solid option which will remain relevant if you ever switch to lightning breath is quick riposte. Since the most aggressive units in the game have speed in the 40s if not 50s, Y.Tiki will have a hard time doubling them without QR. With QR, all you need to do is prevent their double, and the skill will take care of the rest.

Your C-skill could be used to buff the team, but atk smoke definitely seems like a good option. It's almost like gaining +7 def/res after her first combat, which can help a lot especially if you're using renewal - just survive a little longer, and you heal about half your max HP. With fury, (unless you have -res IV), you're also getting into territory where you can debuff your opponents using ploys before you ever enter combat. It won't work against high-res mages such as Micaiah (and if I remember right, Deidre - who any dragon needs to be very careful with - also has quite good res), but it should activate quite reliably against most melee attackers, and it will definitely work on the glass cannons, those most aggressive units who abandon all defenses to hit as hard and fast as possible. I don't know if you have a unit to sacrifice for ploys, though. If I were to give your Tiki a ploy I would probably choose spd ploy. Deidre and Micaiah are not fast mages so you don't need to worry about being unable to ploy them; the really fast mages actually won't have enough res to dodge this ploy, so you greatly improve your chances of preventing a double.

Since you have such a nice Y.Tiki, I wouldn't spend your feathers on A.Tiki. If you like dragons, I suggest Fae or Nowi.

Wish I could play your Tiki! Seems like lots of fun!

You already have a distant counter red on your team so doesn't seem worthwhile to make Tiki into one. I would recommend Quick Riposte 2 from a 4 star Subaki for the B slot. Smokes are amazing C slots although a bit rare, I'd guess Spd Smoke would be slightly better, but Atk Smoke is available at 4*. Otherwise Drives, Hones, and Tactic skills are generally useful. If you refine Breath of Fog, you might want to consider the SPD refine since it would get her up to 39 speed.

With Ike's Def Tactic buff she's going to be a great enemy phase unit versus melee enemies. If you ever get Atk Tactic fodder it would be amazing for your team on New Year Azura.