Yes, with first-party data you can run retargeting ad campaigns and offer personalization as first-party data is fully privacy compliant.

There is no one-solution that fits all approach. Every business is different and the way the user interacts is different. Therefore, after collecting the first-party data and analyzing it, you have to come up with customized strategies to boost your business.

Ad platforms such as Google & Facebook have default audience segments that give you good results. However, if you want to understand your audience better & retarget them, you would need better segmentation features which are not available on ad platforms. You have to depend on a real-time CDP such as CustomerLabs to implement advance audience segmentation to understand your audience better and get great results!