Changing log level and properties from HAC is often used by developers for various support things. Unfortunately on SAP Commerce Cloud (CCv2) there is no more such possibility, as HAC is not available on storefront nodes.
In article SameSite cookie issue in Hybris is described, how to fix issue with SameSite cookie attribute. But, unfortunately, it is not working with enabled session persistence.
Modern web development tend to use fronted frameworks with API rest calls to hybris backend. Such approach skips hybris CMS caching system and can lead to performance issues. One of the possible improvement would be to utilize caching on browser side and in such way decrease amount of requests send to server by browser.