Communications crystals would be far more popular if they were easier to set up. For example, unlinking a link would be a really handy addition, as would "resetting" a crystal to break all links. Also, to encourage their use, comm crystals should not charge extra for more links (i.e. a comm crystal with 5 links still only uses one charge). But this is only the beginning of how to make comm crystals truly useful...
Travelling off to a cool-feature-far-away land: there ought to be an expensive variant, an "enchanted (?) communication crystal", which is newbied. That way you could basically set up an in-game, in-character, permanent, worldwide communication tool. The existing (T2A) "in-game" chat system is not entirely useful, because it's not really in-game. Same for the in-game e-mail system being developed for GMs that they're talking about letting players use, one imagines. Both of those systems are out-of-character and require switching away from the gameplay window. But the existence of such worldwide communication systems indicates that Origin realizes people have a need for such a tool. Just make it easier to use, and make it in-character, and you have a winner: in other words, comm crystals.
This leads to a bit of a leap, to a system of in-game cross-world chatting that is actually in-character using these comm crystals. Maybe if the "enchanted (newbie) comm crystal" item was implemented, it could eventually become part of the game to the point where there could be a hotkey assignable to "Enable Comm Crystal". Ideally, instead of a hotkey, there would be a special character combo at the beginning of your line of text that would indicate "use my comm crystal". "@{space}" could speak to the crystal, like ";{space}" does for whispering. A further enhancement would allow you to choose which of your comm crystal's links to use, so that you could communicate magically with just one (or just a few) of your comrades: "@ reana Let's kill Ladnar".
In addition, crystals should be "nameable" (one supposes targeting a crystal with itself might do this) so that you could easily see which link a crystal message was coming from: "Faramir's crystal: BlUdLuSt says Corp Por".
The question then would be how complicated it's worth making the interface to comm crystals (a whole gump of links? seems like overkill but how else to remember who's on your links?), and also whether or not newbies should get one for free.