I think that creating new anomalies would go a long way in keeping the anomalies fresh.
Otherwise, exploration might lose some (but not all) of its charm after a few playthroughs (the number of which would be dependent on the number of the anomaly and the player's zeal in searching for them, I guess).
I think that another way they might keep us players on our toes would be to have different anomalies in the same "package", so to speak, e.g. the 2001's monolith-like anomaly discovered in the Blorg stream was found out to be a library. Perhaps another monolith would give the same anomaly text when encountered but if successfully investigated would, for example, give the scientist charterer experience and a rare trait (the monolith was a defunct uplifting device created by a precursor civilization; when activated it enhanced the mind of the scientist before crumbling to dust)
This will help prevent the feeling of "yeah, I know what that does" that goes against the concept of discovering the unknown.