Product Marketing OKRs are really important to keeping teams focused on driving the most impact for the company. At a Product Marketing OKR level, it often depends on what the company goals are for that particular time period. If the company is going after a new market or focusing on customer retention, that's going to influence what a PMM's KR will be.
Second, I think it's importnt to set a KR that you have direct influence or impact on. Sometimes, PMMs at Lyft share KRs with PMs, but ideally, there is a sub-KR that indicates whether a PMM's investment of resources is succeeding at supporting the overall KR. Most notably, what a PMM can influence directly is product/feature adoption, sales enablement success (for B2B), and active user growth. I advise my team to use 'absolute' KRs sparingly and only if there is no other option. For example 'Launch new marketing website by Q3' would be an absolute KR. I would suggest to think about 'why' we're launching a new marketing website and what that will do for the product or company. You may revise the KR to say 'Launch a marketing website that results in a 10% increase in self-service signups by the end of Q4'. In this example, we've pushed out the measurement to Q4 and determined directly in the KR how this work will move the business forward.