I didnt really care for the native gallery app either. If you have Astro File Manager, you can browse directly to the folder that has the pics you want to see and Astro even has it's own photo viewer built in that I prefer over the stock one
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. If you want to set up a slide show, search for a free app called "Photo Slideshow" It has lots of options for presenting a slide show and after it's all set up your always just one click away from a slide show of your favorite photos. Those are the best solutions I've found, if you need any help setting up Photo Slideshow lemme know