Well ! I have been trying to give you something that may be compelling, but I must admit I can only come up with small advantages but these are countered by some challenging disadvantages.
I have 5mtr hyperlink V1 ultralight, and a 7mtr v2 hyperlink
My 5mtr is my highwind kite, the 7 is not a highwind
tool for me,
I bought the 7mtr for high winds but found its range was so large I regard it as my brisk airs fun kite, for over 15knts, although it is happy being taken out in steady winds much much lower, on a 633 wing,
some guys over 95 kg on flag beach have this 7mtr kite as their one kite quiver
My 5mtr comes out when the winds are over 20knts, I can take it up to around 29knts and it's still loads of fun with little or no depower engaged, but as soon as I have to depower a bit more, then the fun factor drops dramatically and I avoid downloops unless I feel a lull, getting hooked through the air at full thrust by a foil kite, even a 5mtr is a wild experience. I have not given much thought to maybe getting a smaller foil,
30knts for me on the open sea is about my limit, after that its not much fun, more like hanging on with kite high and bum cheeks clenched
I have had both small foils for a while now, well over a year, and both kites re-launch by "themselves" in stiff winds, the 5 just bounces back into the air, sometimes before I am ready, so no disadvantages with relaunch, 100% success for me
number 1 disadvantage
against a small lei would be launch and land, launching these kites in their upper wind ranges
is easy, but needs practice to get dialed in, landing in high winds again needs practice, and although you can land unassisted, an lei self landing is less stressful.
Body dragging out through shore break in onshore winds is the foil kites very strong point
, it will never drop in a lull or when a wave pushes you back, and points high into wind pulling you through the worst mush at high speed to get to clear water,
Another foil kite plus is you drop the kite far less, I can run towards mine without too much slack line and if I do get slack line its much easier to "catch" the kite as it never tumbles down like an lei can
To hit the water with the small foil you have to steer it in, and if you roll the kite through the lines it flies just fine, no need to go ashore,
lift is always there with the 7mtr, It is a great boosting kite with softish landings possible, not too technical at all, boosting with the 5mtr is easy however its hard work to land without getting wet, same as a small lei.
Power delivery- a foils linear power delivery especially driving upwind is the number one advantage
for me, so so smooth, silky smooth, high and fast, my lei kites just could not score as highly in this respect.
Some would say an lei is cheaper, however I need fewer foil kites and hardly ever need to change down or up like I used to when using lei ktes.
other obvious advantages is the lack of weight, 1.29kg for my 5mtr, 1.39kg for the 7mtr, half the weight of many 3 strut lei kites,
overall a smaller quiver of kites is required, so traveling light is easy, and walking to the water with kite tucked under your arm knowing you are more likely to have a kite that will work all day, along with the absence of the ruddy pump which might get a dog wash, or pinched is such a good feeling, cant remember the last time I needed to lug a quiver of kites down the beach for a session, o yes i can! when I had lei kites
But if all foil kite companies stopped making small foil kites, then going back to small lei kites would not be and issue, loved them! but I love small foil kites a bit more.
I would not consider a peak kite, they are good for some, but for me and where I sail, no thanks! tried one and I can see why they have a following, but as you can see from my likes above they are not for me.