I'm just going to say--P, 2P and BT6K are Ayane's best single pokes, hands down. And I'm not going to say why either. This time, I'm going to let you guys take a good guess at it.
I want to see if we're actually on the same page.
P = Fast startup at i10, only -1 on block, one of the safest and efficient ways to enter BT stance (and to bait reactions by transitioning back to FT with P~BT8P). Excellent way to transition between FT & BT mix-ups seamlessly, along with P~BTH+P being one of the best (if not the best) tick throw setups in the game. A great move for frametrapping slower characters when coupled with...
2P = Best low jab in the game at i12, 0 on NH, -4 on block and great range at approximately 1.46 M. This move combined with P can frametrap and lock down quite a lot of characters, especially characters that have i13 mids and lows or slower. Just the i9 jabbers/i11 mid strikers can really break the frametrap effectively. There's pretty much no downside to Ayane's 2P and it can even be used as a keepout tool if you wanted because of the pushback on CH, especially if you can hit the opponent at tip range. There's also the beauty of the Low Jab Trap pressure technique, where you can frametrap opponents by just doing 2P over and over and then eventually poking with either P, 6P, or 6K for example. Annoys the hells out of characters that lack i12 lows, and have i13 or slower mids.
BT6K = Decent speed at i15, slight advantage on NH, SDS on CH (and bound on critical threshold hit), 0 on block and +1 at tip range. The risk/reward for this move is in your favour for the most part though spacing that tip range hit on block can be tricky. The SDS on CH is amazing thanks to getting either a free 4K bounce launch combo or a free 236K and further ranges for a nice blast back hit. This should generally be your go to Mid K from BT unless you're out of range (in that case BT4H+K reaches further). BT4K suffers from being unsafe on block despite having good range and a pretty good launch.
Yeah, I spam these moves sometimes...