Hi All
Thanks for all the responses, each one very interesting indeed!
I decided to do it another way, a low tech approach

I will make each template that needs the variable number of images a container and create another template to store the image + caption + description.
Then make create children of the posting with the template that needs the images with the "image-template" and add a snippet that displays all the images on the children nodes in the parent template.
Simple but I think effective.
There’s just one thing I’m missing to really be satisfied by this approach, is there any way to add new pages from the "quick editor"?
It will be nice to have a way to add children pages directly from the quick editor!
Regards and I hope this post helps people exploring this kind of problem.
Regards
Vlax