App Store Marketing Strategy Consultation for Financial App

We recently launched a financial services app on ios. The app offers an initial 14 day free trial and then is $6 per month thereafter. We were running ads through an AI/Machine Learning focused app marketing company and were receiving a fair amount of installs but we were unable to optimize for actual registrations as our conversion event with this app marketing company. I have since familiarized myself with the limitations that exist around targeting specific users based on demographics due to many opting out of tracking after the recent rule changes on Apple. Because of this I am in need of an experienced professional who can walk me through the benefits and cost of each potential marketing channel we should be using to optimize for paid registrations after the 14 day free trial has expired. I imagine we would do an audit of our existing creatives, website, landing pages for email signups, and then dig into the screens within the app itself and see if there is anything we are missing as far as optimizing for registrations are concerned. We would also go over our google analytics reports so far and see if everything is connected correctly for data tracking. This will start as a one time marketing strategy call after which I would expect a list of actionable items for us to implement and recommendations of specific channels and tools we should be using moving forward to maximize our app store marketing strategy as part of a smooth multi-channel funnel.