Just go on learning with the 633.
Yes you need power as size is small and less lift because of lower AR, but it will work, and also have a very easy stall behaviour, fine when learning.
The good thing is, most wings having a span around 90 cm and higher, are really slow turning, I hate that myself.
But one need to make a compromise, if you like to ride waves and surf/glide.
My 91 cm turns a bit slow because of the span yes, my 85 cm is much more fun carving - but the 91 cm has a lot better glide and starts earlier, so my most used foilwing now.
The point is, one of the first things I remember learning after the initial "learn to control and ride straight in control", was to carve around swapping the wing, and then carve back again on a small wave - felt great, and so much better with lower AR and low span wings.
Or swept and anhedral wings - better turning more lively, but partly on cost of glide.
So eventhough you dont get the glide and early start, you get a much better turning wing, so enjoy this instead, when you eventually reach this level
I always see "lateral stability" as a very negative property, as it means dull and slow turning and in my eyes no advantage in itself
But as it is always connected to wings with better glide, this compromise must sometimes exist.