Hi Eric,
With your current level, you should be able to take any of the courses you mention.
They don’t really have an order in which to take them. All are really fun to do and cover a lot of different techniques.
Assemble is, as mentioned above, indeed very technical and concentrates solely on Geometry Nodes. Astray and Stylized Forest require a more than minimal computer. Otherwise I agree with @Secresteyn , just choose what appeals most to you.
