Need help with B&W CDM 1 SE’s

I have a pair of 25 year old CDM 1 SE’s driven by a Bryston B60 amp. To my ears (admittedly aging) they sound flat with little base and muted highs. I have read that the ferrofluid in the tweeters is known to dry out and requires changing every decade or so. Would doing this make a significant difference, or just a subtle one?

I’ve also seen several entities which advertise upgrades for the speakers at a cost of $300-$400 dollars. If anyone knows what parts would be required, and whether it would be a worthwhile thing to do an upgrade of the crossover, I’d love to hear ideas and feedback.