Thanks for the post and for the feedback - we’re always keen to hear how we can improve.
First, I can confirm that it’s not possible to change the color of those icons. I’ve already filed a ticket with our dev team to ask them to consider it.
I hope you understand that many feature requests like this are considered but ultimately not included for a variety of reasons, not least a desire to limit complexity. We’re passionate about the fact that we’re a low-fidelity tool. We believe that having fewer choices at the ideation stage leads to a focus on ideas rather than the presentation.
All that said, thank you again for the feedback - it’s very much appreciated.