Here are a bunch of ideas.
Trade out your designs for holiday fun! Highlight them with battery operated lights, with a timer.
Heres a few photos
For summer, I decorated mine with seashells from our vacations: https://www.simplicityinthesouth.com/simple-summer-decorating-ideas/
For Spring and for most of the year, I keep a plant under the cloche: https://www.simplicityinthesouth.com/easter-decor-display-turquoise-chalkboard/
Although this isn't inside, it shows a large collection of shells. These on a screened in porch in summer