Legend:
I don't find the new change to be very useful. Sure it can give you a good production rate for one round, but so can many restoration cards, and also most secondary effects on Legend cards already give you a production boost, therefore the current keyword effect is a bit redundant in my oppinion. The facility increase was much better since it gave you a more long-term effect on your resources which could make you able resist brigand decks more effectively. Without the previous keyword effect, the Legend keyword is not much worth having it in my deck.
Alliance:
The effect that gives now gems production increase is again useless in my oppinion. We currently have 3 keywords that result in almost the same effect: Mage, Alliance and Rebirth. It would be better if the previous effect was restored, as it gave an overall resource increase which meant you could use this deck to achieve resource accumulation victory. The current effect just makes it good to combine it with Mage decks, which can pretty much sustain themselves in gem accumulation, or combine it with Burning decks, which already have the Rebirth keyword as a supporting keyword and can have massive gem accumulation, and it's far better to combine them with Mage decks instead (much more catastrophic, higher gem increase)
Anyway, this is just my opinion, I might be wrong but I really think changes in these keywords are unnecessary.