I'd go for it. It's never the right time. You'll progress with the challenge. I myself switched to a 60l board at 80kg bodyweight when I couldn't do any tacks and maybe 80% of jibes. You'll learn the stinkbug start real quick and then it's basically no different than a big board. Only exceptions are that you cannot slog home when the wind dies and you cannot get up on foil on short gusts as it takes a few seconds to get to your feet.
But other than that no disadvantages in my opinion (granted I ride in flat water).
With the smaller board I progressed much quicker than before, it's just more reactive.
true, but you could layer it. regarding the yellow gong shirt I must say that it is not very comfortable, the material is quite harsh/abrasive, so it's a bit rough on the elbows and especially on the nipples.
I have the gong stuff (shorts and shirt) but recently "upgraded" the shorts to the ion surf shield. the pants are quite comfortable I must say. Not cheap of course, but if they prevent an injury it's worth it for me.