Now that we are on the path to needing to support much more complex image variations, how do we go about preparing, managing and serving them?
One option is by using local/desktop workflows to more efficiently create the multitude of variations of size, compression, dpi and even crop-to-point-of-interest that you may now need for every one of the images across your site.
If we can be sure that there are a small number of variations needed, then this might be a feasible approach, however it also relies on expecting very little or no changes to the way that your website will be consumed in the future. Otherwise even relatively small changes like applying greater image compression across all category/lister images in order to compensate for performance concerns, or provide higher definition assets due to the release of newer, even higher definition devices, can start to inhibit our options.
From a maintenance and flexibility standpoint, for even a relatively small site with just a few hundred images, these challenges, can very quickly become restrictions on the flexibility you can afford your website, and restrict your ability to adapt your content to changing device and technology ecosystems.