Well, I guess you are not reporting anything bad happening so far!
You can look in Menu: File → Database Properties to give you an idea how many words you are dealing with now.
I don’t know how “hard-core” the limits you quote are. The experts can weigh in …
Given the linking/replicants that you seek, I still think you are better off working in one database. If you are concerned of the risk you perceive, maybe some of your files are not candidates for your linking/replicants and can reside in another location/database until you find a need, or something,
Meantime, search in this forum for where this question of “big databases” discussed already, e.g.
