Just to mention a few suggestions:
windmill, 4-beat, both directions
corkscrew, 4-beat, both directions
butterfly behind your head
butterfly behind your back
4-beat thread the needle
buzzsaw
different kinds of stalls and stall combinations (in all the modes)
body wraps and other direction changes
airwrap
pirouettes
Everytime you learn a new move, new combinations open up to you. After knowing the weaves and your windmill, perhaps go for a fountain.. The list goes on.
...And most importantly at your stage, practice plane control and strive for freedom of movement. Everytime you learn a move, search (atleast) for the following things:
-what different variations are there?
-can it be done in different modes?
-can I turn with it?
-can I do it anywhere around my body? (high, low, to the far sides, with extended arms, with curled up arms, etc...)
-How can I accentuate the move with my body to make it really "pop"?