Hi @nandoanversa,
Regarding the images, yes they will get even smaller if there container became small than there own width, that is the responsive behavior of the Image element, Unless you set a static width on them and large padding and margins on the containers can be a factor too.
I did check your page so I understand why you used such huge padding and margins. What can I advice is instead of re-setting those margin and padding on mobile view, please utilize the Hide During Breakpoint feature. The idea is to have a different container (section or row) for desktop view and for mobile view. No, you don’t need to do this for all your sections, only those sections that become messy on mobile view.
Regarding Accordion, please use the (V2) Accordion Element (not the classic accordion). It has the text formatting and text styling option same as the headline.
Make sure you’re inspecting the Accordion itself and not the Accordion Item.
There are other ways to make your text responsive not only with Responsive Text feature, please follow this post for more details.
Cheers!