Honestly, it all depends on your body and how you ride, mixed with the balance of your saddle, your horse, and the saddle your in. You can measure a million things and still get in the wrong flap on the wrong saddle.
A Voltaire’s “straight flap” is not the same as a CWD as a Butet as a Monoflap as anything. They all differ some. Also if you go deep seat to half deep to flat.
Note that most monoflaps have a more “forward” flap than normal saddles purely due to construction of the saddle. If your a forward flap in a mono, it might not be a bad idea to try yourself in a forward flap in a regular saddle. Howver, since you are short, you want to make sure your flap is also short on the calf or else your going to have no contact at all.
Im 5’6. I ride in very flat seats, narrow twists, and short “long” flaps. It’s my preference for my knee to just kiss the edge of the flap and to not have a lot in front of me while having a short flap under my leg.
when I ride in a deeper seat, i technically could use a shorter more “forward” flap but that encourages me to remain in a chair and behind my horses movement, so if I go deep - I still prefer a long flap with s touch more panel in the back to get me out of the saddle.
My suggestion for you- try again with a different fitter. Sit in as many brands and types as possible. You can measure all the things ask all the shorties, but there are a ton of variables!
- previously a professional fitter