looks also quite o.k. for me.
the A are longer and even the outdated MK4 has a more modern (evoluted) shape than the 4.9 which basically means more volume in front of the bow.

V shape and flat bottom shape are anyhow very different to sail and not really comparable. if you nose dive the flyer in everything than very little wind you are just slow.

basically (like already pointed out) target in light wind is to get the sterns same level with the waterline to have less drag.

in strong wind even the 4.9 has the potential to plane, but for that you have to step far behind and submerge the sterns quite significant, as the boat is still much to V-shaped in front of the frontbeam.

if you look at picture you see how far people stand behind. notice how much spray (and drag) is taken into account just to generate positive lift by planning...

even the hull shape of the famous flyer I believe is not optimized, the flat aft part need still to be submerged to get the boat into the angle to appreciate best planning lift and therefore best speeds.

so basically it's always about the compromise between to much draggy stern and support from planning and if this lift cannot be generated due to lack of speed (wind) reducing of drag on the stern is major target, specially with V-shape hulls.

regards

dirk