Beautiful work, highest respects Bas.
You mentioned earlier:
"Sometimes I get the feeling I have to buy also more software to explore. The danger of it is loosing creativity."
In terms of losing creativity with new software, maybe an analogy would be that you would be learning to play a new (musical) instrument.
You know the music, but until you know the new instrument completely, you wouldn't be able to play freely and "without thinking",
We can't just give a flute to a child and say, "now play me a pretty song". That takes time, of course, to learn.
Your feeling to need more software to explore, well that would depend on what you would like to use it for...
Seems the software you are using now is more than enough for the imagery you are creating. Very powerful.
If you wanted to animate, then yes you would need another soft too for now, and you could learn that.
But do you want to?
If yes... you could do it.
If no...well just keep jamming on your instrument!
May every post be a great one Bas...
and congrats! (gefeliciteerd?)