No offense, but you will find out with more experience, that volume matters
Volume makes a big difference in terms of "how low can you go", when you explore the utmost low end on a hydrofoil, standing fully "parked with zero speed" occasionally, with a given kite, trust me
I stick to the statement, that it is all about keeping the "transition energy needed" from non foiling to foiling as low and short as possible, thus flotation is good when trying to get moving from a standstill
Having the same area, one superthin no volume, the other lots of volume, there is no comparison whatsoever, and you will be able to go a lot lower with the volume board, as you dont waste energi getting to the surface first, and when out in marginal winds where you need many loops, full stops, and pumping and redirections and so on, to start foiling, it really matters that you got volume.
Of course, WHEN we are up riding/planing no matter if a TT or a hydrofoil, volume makes absolutely no difference whatsoever - but that is a totally different issue, and it seems to confuse as these are two different aspects.
Sub planing on a TT if even the slightest forward speed, volume doesnt matter much either, agree.
But it matters for extreme marginal wind hydrofoiling with a given kite, is my statement and experiences.
Peter