Why Archangels is the "Go-to" Mana Item
The issue with the new mana items is that only one out of the three provides enough mana to last throughout an extended duration. Both Ludens and GLP provide beneficial aspects, but still they do not provide enough mana. Sure their base mana is higher than old Morello, but the reason that item solved the mana issues was because of its passive that granted a large amount of mana (35% max mana I believe?) for any assist or kill.
None of the current mana items have this passive, which means that in order to cope with high mana costs, you need an item that can provide enough mana to last an entire duration of an extended fight so you don't go oom in the middle of it. Archangels provides over 3x the amount of mana AND way more AP than the other 2 items (not to mention that super handy shield that is still busted after the nerfs), and until you increase the base mana of the other items or grant some mana % after a kill/assist like it used to, this problem won't get solved.
Champions that should be using Luden's Echo (like Ziggs for example) are simply buying Archangels because they don't want to go oom after a few spell rotations. You need to buff how mana is given in Ludens and GLP if you want them to be viable.
passive :/
: Hitting a champion with the passive effect restores X% missing mana. (similar to
)
: Hitting an enemy champion with this items active marks them for 10 seconds. If they die within that time, restore X% of your maximum mana.