1) I'd get rid of "trending accounts". People can see that elsewhere, so it's not really your value-added and it distracts from the clean design and creates a false feedback-loop for data collection (based on accounts, rather than images).

2) Make the tiles similar (but slightly different) sizes and make sure that they're full to the edges. Otherwise, it looks confusing because of the blank spaces and people will be more-inclined to click on the larger tiles than the smaller ones, rather than only reacting to the interest they feel from the image.

3) Figure out a way to filter-out screenshots of code, spreadsheets, etc. if possible.

4) Arrange the tiles a bit irregularly, so that it looks less stiff. Make the corners curved and get rid of any borders or alignment-lines. Use blank space as the only separator.

5) Filter out audio-only and have videos play in a loop.

6) When a tile is clicked on, open to a larger version of the image with the profile page of the npub displayed next to it.

7) (Very advanced, but this is the important algo bit.) On the single-tile display page, have suggested next-tiles listed below or along the side or something, so that they can choose to click on the npub profile or see more similar pictures.