I guess the images you choose should be somthing you feel are appropriate as a gift to the receiver. You know better then any of us what the lucky friend would be delighted to get.
As for putting together a series, I'm sure, with the verity in imagination you show, something will come along that will burn to be told. Take a step then another and soon you will be consumed in the process.
You may or not know that I have just published my first book. I started it three years ago and after 1,000 words I stoped. Why? because as a disabled person my typing permited me to only type a blazing
10 words a minute. I saw a mountain of a job before me. and felt I it was beyond any effort I had in me. I set it aside for almost a year. Then one day I picked it up again. I pick at it over the next 10,000 words and doing so, realized that time and effort added up to success. Now the book ended up to 67,000+ words and finished
Just start!