1920x1080 is too small by today's standards. If you're going to use 16:9 aspect ratio, go at least 2560x1440. Anyone who is non-retarded can resize down to 1080 just by telling their computer to fit the image to desktop. A 1440 pape usually upscales to 4K nicely, especially if you make the original in high quality, such as 600 dpi (or even 800 dpi), and if you use .jpg files, set the compression to 95% or better such as 98% (which is basically the same filesize as 95% but holds very slightly better if it's upscaled to 3840x2160. Lossless .png is also a good option to explore & use, when practical.
Keep in mind, if you want to 'future proof' your papes so that they're still useful & relevant in 5 or 10 years, people are going to want to upscale them to 8K. And, eventually, higher. So, the highest quality that you provide at the beginning will give them extra, useful life expectancy.
I've had a lot of miserable experiences finding great old images from the 1998 Internet, but you just can't salvage a 640x480 .jpg that was saved as 50% compression at 72 dpi to conserve bandwidth. Explore and maximize quality as much as you can, try to upscale some of your own images occasionally just to see what happens. Take one of your 1080 images from this thread and blow it up to 15360x8640 (16K) just for giggles to examine where it looks good and where it fails. Before you do ANY editing/resizing, the first thing to ALWAYS do is set the DPI at 1200 or 2400. You can always reduce it after the final edits if needed.