Yes, Manwë often shows enigmatic traits of his behaviour, and can be misinterpreted as a 'powerless' King in its own Kingdom (Arda); Tolkien himself writes that he is a very good and merciful being, almost a stranger in the ruling dynamics of the World, who initially believed in the possibility of a second chance for his elder brother Melkor.
This merciful trait of him led, then, Manwë to make great mistakes and suffer the consequences of his good intentions.
But Tolkien also states that he is the dearest Ainu to Ilúvatar, and that Eru 'chose' him because he had understood deeply its Plan, more than any other Ainur, granting him an almost Universal Knowledge of the Destiny of the Universe (not complete though, since he is not omniscient).
We can thus say that, although his choices were initially really suffered and indirectly caused a lot of terrible consequences, he was right in the 'long term' of the events.
For example, after the Darkening of Valinor, while the Vanyar (and secondarily the Teleri) chose to remain 'loyal' to the Will of the Valar, Fëanor (also deceived by the lies of Melkor) accused Manwë of 'cowardice' for not immediately waging war to Morgoth in Middle Earth, disobeying to the Valar and starting, then, the Exile of the Noldor from the Blessed Realm.
But Manwë eventually was, at the the display of the events, right and wise; he didn't move war to Morgoth in Beleriand to not wound another time the World and endanger the recently-awakened and vulnerable Humans.
Fëanor, instead, ended up being completely wrong in his own deep reasons and purposes, since, although the Splendour of the Noldorin Kingdoms of Beleriand, the Noldor never managed anymore to create an eternal and stable realm in Middle Earth, and recreate completely the Splendour of Valinor outside the Pelóri, suffering unspeakable sorrows due to Morgoth first, and then Sauron in the Second and Third Age
Anyway, I definitely like Varda more; she is my favourite Vala along with Nienna.
The Elves immediately fell in love with her, when they reached Valinor