I’ve used a digital projector in the past, but these days, I would say you would be better served by using a 4K tv for everything, or your existing plasma. Easier and higher quality for less overall money at current pricing. Update your receiver to one that processes and accepts a USB thumb drive loaded with 4K resolution photos, either singly, or in a 4K slideshow easily created by one of the available computer programs. No cables. It’s just sharper, better color, easier, less cumbersome, with no downsides relative to a projector these days in my opinion. Google one of the home theater review sites, and do some research there on modern receivers, as I can’t go into all the possibilities here. Would also be less expensive than the amounts you were considering for a nice projector. Not telling you what to do, I just don’t think digital projection makes sense any longer.
Best wishes with your experiment, it’s worth it.