I can only agree, the Pulsion 15 m2 in 27 g cloth is EXTREMELY stable, and can hang in ridiculously low wind
In fact, it is the only foil kite I have never had in the water yet - it hangs in less wind than I can foil.
I am pretty sure, that higher aspect kites if similar extreme low weight, got more peak power (those I have had, but heavier, got more peak power) so in theory you could push the low end in marginal winds even further.
BUT, in reality you can not, as they will collapse easier and you can not survive the extreme lulls the same way as the Pulsion can.
I dont know about the Peak4 in the bigger sizes, but my take would be it has too low peak power to reach the same low end, eventhough it seems they work great in the smaller sizes for waveriding, but a totally different scenario.
With long lines, which are needed, 30 to 32 meters is my choice, the higher aspect kites can pull when looped, even better than the pulsion, but they are too "fragile" and can drop or collapse really easy, thus I have found the Pulsion to be the best practical weapon for pushing the low end without swimming
In 3 to 4 knots I can keep it in the air easily, and of course keep it flying looping in less wind.
But need around 4-5 knots with my 78 kg, to have a chance to foil, with the right wing and board, depending on wind quality of course.