I am not sure how Acronis works, but here is how we work...
The first backup is a full backup, all the following ones are incremental ones. After the defined retention that you have selected, the full will be merged with the one after that, making the oldest recovery point going away. We will get more into detail in this process later on when we are GA, but we use the forever incremental process which you can read in our manuals on Backup & Replication.
For the merge process, it should not be painful at all and considering the way we make sure that the process works "slower" if needed (when you need the resources) you should not suffer from it.
But don't take it from me. Take a retention policy of 1 or 2 days and see for yourself