It's impossible to recommend a shaft based on your desire. You need to work with a qualified Titleist Fitter and see what recommendation comes from the fitting session. It's the only way to get the correct shaft/head combo for your game. Look for a Titleist Thursday event in your area (free fittings). In the mean time, take a look at the Custom Clubs Options booklet to see what iron shafts are available with their associated uncharge cost (if any).

media.titleist.com/.../2018 Custom Price List (Q2).pdf

I went to the KBS C-Taper Lites from that shaft to lower the trajectory when I first went from 712 AP2's to 714 AP2's, then had the same put into my 718 AP2's. Weight is very much the same but the flight is mid instead of high. At least for me, I liked the feel of the NS Pro 105's and the C Taper Lites felt as good if not better. However, that is just my preference and best fit.

The link below will take you to the actual Custom Club Options booklet...not sure why the booklet with cost data listed was on the link this morning.

media.titleist.com/.../Titleist_Clubs_Custom_Options.pdf

Getting fitted is the best way to tinker with different shafts. That being said, I would personally recommend the True Temper AMT’s (the shafts gain weight as they go up). The three different options available vary in initial weight. I have the AMT whites in my 718 Ap2’s and absolutely love them. The lighter shafts in the 3-4 are really noticeable, and help to get the ball flight up. The heavier weight in the 8-9-PW is great for taking fat beaver tails out of the fairway! Enjoy those Ap2’s, they are such a game changer.