Next time you see Premiere Elements on sale, consider it for your 4K slide shows. Oddly, there is more support for slide shows than in Premiere Pro. Premiere Elements can read RAWs from Lightroom Classic, including the Develop adjustments if you have the XMP option on. Premiere Pro can't read RAWs at all. On top of that there are more options than in Lightroom for things like titles, motion titles, transitions, music tracks and narration. Premiere Elements has good 4K output for any media playable in current TVs like a USB memory stick.
Premiere Elements does have a free trial if you want to play with it!