as you get close to gross weight and an aft CG, there's a noticeable difference in the landing flare. None of it is dramatic at all, just noticeable.
I'm not sure why you're asking but in terms of handling, the weight (a pax and full tanks) seems to me to make a bigger difference to the feel of the plane than the CG shift. Additionally, as you get close to gross weight and an aft CG, there's a noticeable difference in the landing flare. None of it is dramatic at all, just noticeable.
Besides, as you get older you may find that the limit of endurance is not the fuel you carry, but your bladder.