"Suggestions are warmly welcomed."

Ok. :o)

The central work is a rather strong graphic and presentation, in and of itself, so ...

Don't think that you would want to deviate too much away from that. Nor, clutter the final presentation. So ...

How's about tiling a border, along the lines of repeating the graphic you created ... as insets of that border and in essence, forming the border/framing?

And then perhaps, a grid of lines ... receding perspective and relegated to a single quadrant (or two, for compositional balance?) ... to draw your viewer's eyes in, literally.

Lower third alone might work, coming up to, or slightly below the 'points' of your shape and at that demarcation. Lowering the opacity of this element compared to that of the central shape ... so's as to not overpower it.

And ... done.

The gradient you have happening in the background works well and is well placed.

Allll that said ...

'Serendipitous creativity' ... gotta luv it. :o)

Hi Levhi,
I preface my remarks with the information that I use The Gimp all the time, but for photo manip and fractal manip, not for creating images from scratch, so my knowledge about what you are creating is limited. I can suggest that some of the lines need to be smoothed out, eg if you go to the base of the middle "tri arrow" spike at the top and move left or right you come to "bumpy" bits where the joining of lines is easily seen. How to add dynamism? Something I add to the background of fractals is is a starburst background - lines radiating out from a central point, can be sharpened or softened to suit. If you wanted to move away from the simplicity of this current design then how about some kind of shadowy "deathshead" skull as part of the background, mostly shadowy, a bit larger than the current yellow image? Just throwin the ideas out there. :) As a general rule I think illustrators and artists of your ilk need to be thick skinned on Caedes, in terms of the c-index, the voters like "dramatically pretty landscapes" and the punish anything else mercilessly. I think the central design is bold, simple and interesting and has metaphoric potential with it's elements of "mask" and "choices/directions".

Wow this is very creative and the design is so amazing