Ozzy, I have a pair of refurbished Duetta Signature which are similar to your Clarysis. Please avoid all theorical acoustic suggestions coming from non-planar speaker owners. Panel speakers have a figure 8 diffusion pattern and require specific acoustic solutions. As Suncoast Audio suggested, only use diffusers behind your panels. This is what I have successfully using for the last 10 years. You will enjoy a larger and deeper soundstage with increase imaging.
Personally, I have built my own wood diffusers using 2x2 inch square studs. You can find this DIY diffuser recipe on the web. I have installed them at ears height directly behind the mid/high ribbons. Afterwards, I installed the same DIY diffusers behind my listening area at same height and line of sight as the front wall diffusers.
These provided additional benefits (no more walls Ma!). Total cost was about $200 for four 2 square feet diffusers.