A few observations that can help make the design more crisp and consistent.

• The triangle pointer on the edge of the frame is unnecessary. Feels a bit childish, like a LibreOffice or Powerpoint-like environment. Also does not match in directional sense with the black triangle above it.
• Behandel het zwarte driehoekje als "more" symbool als andere.
• Frame has too thick a line in my opinion, a bit blunt.
• Be consistent with color and gradient swatches;
  – frame or no frame; (none imo)
  – square or rectangular; (square imo)
  – too much drop shadow, preferably no drop shadows behind (gradient) swatches (dirty).

An exercise
On the left the original, on the right with adjustments