Hi there

Thank you for asking, in general if it is in line with my copyright license it should be fine. And as you requested it here there should not be a problem as long as the license is followed up on. So attribution as you mentioned already. You can do this just by name or also include the original link to the image, that it isn't monetised or used for commercial purposes and that it won't be derivatived. Besides that go ahead and feel free to pm me the link with the final result. 

Awesome! Glad you like it

3D programs like blender and post render altering in pixel programs like photoshop or affinity.

I do not really have a tutorial, but I do have the history: www.rafaeldejongh.com/synthwav…

My copyright states that NoDerivatives are allowed, so no I can not allow this sadly.

I do commissioned work yes.

This depends, are you going to sell your playlist on spotify or are there any commercial benefits linked to this or derivatives? Those two are the more important ones rather than the attribution.
Feel free to enlighten me with what you have in mind then I can provide the necessary permission if it seems fit!