Struggling to choose template and customizations for Art Portfolio. Missing features.

I am frustrated. What I want to do with Squarespace should be fairly straight forward IF it's a system designed for presenting artwork. I'm a painter who doesn't want to spend any more time than necessary being a web developer (been there, done that professionally). My current site is... old. Creaky. Breaking. The code isn't compatible with more current versions of php and mysql, doesn't offer some responsive features, and I'd rather not rewrite everything.  

What I need beyond the usual (responsive, etc):

1. Multiple portfolios of images using a masonry layout (if I wanted all of my paintings to be square, I'd make only square paintings). 

2. Each image links to page with large image, title, image information (medium, height and width), location if at gallery or in particular collection. 

3. Navigate between image pages with a swipe or arrow keys.

4. Ability to categorize images.

5. Easy to add and update artwork entries.

Strangely, the old Wells template gets somewhat close. But it's, obviously, showing its age both in design and functionality. 

Maybe I'm asking too much. Suggestions?

THANK YOU,

Scott