One of the worst offending annexes when it comes to the hard ceiling of the annex limits is the Loadouts annex.
The HCDB/HCDB2 has tried to alleviate the pressure on total number of entries in that annex by sharing Loadout entries across multiple platforms when it comes to their 'Ferry' mission.
In other words, multiple aircraft of varying types with a roughly similar ferry range value now share a single Loadout annex entry.
Assuming annex limits remain, one way to potentially alleviate the pressure would be to create a new field in the Aircraft annex for 'Ferry range'.
This would eliminate the need to create 'Ferry' loadouts altogether, and free up hundreds of Loadout entries in that annex.
Its kinda ugly, it has potential side effects, and its just one example of where the annex limits create headaches for DB editors.
Random thought.