Or are there better options that I have overlooked?
You can lower retention period and use reversed incremental mode, instead of forward incremental one. Reversed incremental mode is more space conservative. Also, with this approach the latest backup will be a full one (that will be then copied to tape mediums on daily basis) and the oldest point will be deleted, as soon as the retention is reached.
Since it's nothing but a staggering area, you can even set 2 as a number of restore points to keep.