Sometime ago I asked on Moddb's coment section why the Team had eliminated two of the most unique Imladris features in 3.8.1: The first was the way Imladris gained their spell points through the Sages, instead of through fighting like all the other factions. And the second being that Imladris' units didn't need to gain experience, only leveling up once through the Banner Carrier upgrade, and the logic for that being that the elves of Imladris had already attained the maximum expertise possible in the art of combat throughout their very long lives.
One of the Team members (I'm sorry, I don't recall whom it was) answered that the reason for the non-implementation of the first feature in Edain 4 was because the whole sages/library system had changed, which is a fair enough reason, I believe. And the reason for removing the second feature was because they thought fighting and leveling up units is simply fun by comparison with the old feature.
I came here to make some suggestions and argue otherwise. I loved how Imladris didn't need to descend into fighting in order to become stronger, it makes total sense with an isolationist "enclave" (that is not even a realm, mind you) that was created as a haven after the destruction of Eregion, and that has never entered war, and was founded exactly to avoid conflict (with the exception of the war that banished the Witch-King from Angmar, if I'm not mistaken). Well, all that concept/lore is nice and good, but we need mechanical reasons to make this work, so here goes my suggestion.
I really prefer a "real-hero" Erestor, but I'm not gonna argue about that here, and I'm going to think with the current Erestor that we have. So currently if you put Erestor on a resource building he'll provide increase in production, and if you put him in a recruiting building he'll decrease recruiting time. My suggestion is, make it so that the player gains spell points when Erestor is put in the Library. In this system that would be the sole way a Imladris player would gain spell points in the game, not through fighting. Or you could change it to the Citadel instead of the Library.
On the second feature, I must say that I genuinely think it's not that fun to level up your units compared to just have them be the most experienced combatants in Middle-Earth. I loved in 3.8.1 that I could just make them (even more) awesome with an upgrade instead of resorting to violence, which completely fits Imladris' theme. With this feature I really needn't worry about them, only to see which had a banner and which didn't, and could concentrate in other aspects of managing the faction. Thus, coming back to this older feature would go really well with my first suggestion, in which I wouldn't need to worry about leveling up the units, but I would need to worry about an idle Erestor and my spell points. Banner Carrier would be more expensive of course, and weather or not this system is re-implemented, I really think Banner Carriers should be available when the Barracks reach level 2, not 3.