Another question to always keep in mind is how long is do you want to keep the tran log/differential backups.

If you have a business that is doing a hundred new sales/transactions/entries per hour and someone does a mass delete that you know about twenty-five minutes later then you want to get as close as possible before the delete.

But if someone purged last year's record by mistake and you discover it two days later are you going to want to do a PIT recovery to two days ago and lose all the the current data?

Or are you going to do a parallel DB restore and find a way to move the old data across? And if it is a delivered app/db can you do that? That needs to be built in as part of DR planning process.