there is plenty of room on your rails to move your saddle forward on this post... try that first and see if it helps.
as to it making the saddle "seem" higher, why not just raise the saddle? with your saddle leaning back like that, you will be compensating as you fight slipping backwards on the saddle... may be very slightly but may still make a difference.
it may also be that the frame is not too long in the top tube, but too short as well as too low... best off experimenting like you are planning to. I ride a 61 cc st x 57 tt
there is plenty of room on your rails to move your saddle forward on this post... try that first and see if it helps.
as to it making the saddle "seem" higher, why not just raise the saddle? with your saddle leaning back like that, you will be compensating as you fight slipping backwards on the saddle... may be very slightly but may still make a difference.
it may also be that the frame is not too long in the top tube, but too short as well as too low... best off experimenting like you are planning to. I ride a 61 cc st x 57 tt