Building pages by assembling Content Elements of different size and medium

Hello, I am about to build a Portfolio for me as a graphic designer.
CMS Based. More than 100 Projects.

I need 2 different formats: a) Full width b) Half width (side by side on desktop)

Fig.1 Shows a simple situation. Easy, two Multi-image collection fields and it’s done…
Fig.2 But sometimes I need the Half width content to come first.
Fig.3 Or even have a mix of both formats.
Fig.4 I will need to mix image and video.
(including video in the side by side half width format is a plus not a must)
Fig.5 I have more specific content like Soundcloud embedded files.

I was thinking about creating different Content Elements being either full or half width, and then linking them by a multi-reference collection field to the concerned Project. But I did not find a solution.

Perhaps someone has a very different solution…
Thank you

Here is my public share link: LINK
(how to access public share link)