In regard to Alice's spiritual quest:
Alice seems to have certainly inherited her father's sense of introspection. Additionally, she was most familiar with her mother's preference for the "simplicity" of Lutheranism, especially as opposed to the formality of Anglicanism. Those two propensities alone would give rise to her need to question.
The Strauss influence appears IMO to be a path of assurance for her rather than one of confusion. Quite simply put, her doubts were attached to organized religion, with its intrinsic "statutes" of every version, and not to faith itself. That romantic (in the literary sense) journey seems to have provided her with a well-grounded and, importantly, self-determined sense of faith. Gerard Noel cites her words from Kenyon's book:
"THE WHOLE EDIFICE OF PHILOSOPHICAL CONCLUSIONS WHICH I HAD BUILT FOR MYSELF, I FIND TO HAVE NO FOUNDATION WHATSOEVER; NOTHING OF IT IS LEFT, IT HAS CRUMBLED AWAY LIKE DUST. WHAT SHOULD WE BE? WHAT WOULD BECOME OF US IF WE DID NOT BELIEVE THAT THERE IS A GOD WHO RULES THE WORLD AND EACH OF US?"
These words seem a solid truth, the result of a long personal quest, culminating in her acceptance of Frittie's death. At some point, (citation I cannot locate right now), she stated that she felt the need to pray. Her conclusion, then, seems to be one that is based on a faith in God, who can be reached individually.
In an age of questioning and discovery, her solitary journey seems to reflect a personal assessment constituting a balance derived not only from a consideration of science- and philosophy-based uncertainty but also of a personal need to understand her role in her world, if not the role of each individual in her or his own world. There's a newly-spun (chronologically, for her in her time) Wordsworthian certainty about the harmony she creates in her own mind.