I use ImageOptim to optimize images before they get added to a website.
My suggestion here is to add its' features as a service for the forum. Why? For a few reasons, it optimizes images losslessly. This has two effects, faster load times, less server load. It's a total win win.
The above image shows the results of using ImageOptim to decrease file size for this very image which is a PNG screenshot. A 35% image reduction, however you look at it, this translates well.
So if someone here could seriously consider a post image processor to reduce image size it will have an impact on the server hosting this service and cascade down to user experience. Please consider looking into a solution, be it a script or something similar that sits there and intercepts new image uploads and does a single task, reduce file size losslessly.
Please consider it.
Dave, I was wondering though, the site runs on Wordpress as per the source code. I know very little about Wordpress because I don't use it now for years but I suspect there is a database of images somewhere. Is it at all possible under the current configuration to run a script that runs those open source technologies that imageoptim relies on?
I will contact the good folks at wpForo, maybe they have a handle on that. I think it could even be good marketing for them to highlight lossless image compression.
Oh and maybe EWWW is already taking care of it as you have it installed.