How to Create Unique and Creative Presentations Using Gamma and Avoid Low-Effort AI Templates

I just got out of some school presentations where they utilized Gamma to create their slides & though they got it done. I feel like because they put in low effort with Gamma it generated a in consistent and cookie cutter presentation that instantly looked like gamma and I would call this AI Slop. Just in the sense of low effort put in. My question is 1. how do you stop this? 2. I want to be able to make it so slide shows are not so easily determine to be Gamma as well as create better more creative backgrounds. 3. Can we import our own custom icons, layout objects, so things can be more stylized?