I have fast cloud hosting, cloudflare cdn, wp-rocket premium, image sizes are optimised, but my site speed is still very slow 15sec.

I have a lot of dom elements, I use listing grids, so my pages are quite heavy, but I don’t want to remove the functionality.

What can be done to improve the speed times to <5 seconds.

is there hope, or is this the best I can achieve?

my website is here hhtps://horizonbookstore.com/

I have tried different configurations in wp rocket and cloudflare and have them set up as recommended.