Maybe you're right about the institutionalization being the distinguishing characteristic between religion and faith (faith groups). Another possibility might be that religions are centered around a Deity or a Revelator or maybe just any single individual, or maybe a doctrine.
It has seemed to me over the years that many of "the new age" have a bad taste for "religion" but still have need for spiritual awareness, and frequently also a need for a faith in something because they know that they don't have all the answers.
The acquisition or acknowledgement of a personal faith would then precipitate a desire to have that faith acknowledged by another, and soon there arises through conversation and mutual desire for commonality, the seeds of a "faith group" which may go on to become institutionalized without becoming religious, that is, without discovering and acknowledging and naming any deity.
Examples of this are perhaps the humanists and atheists which appear to be institutionalized. It could be argued that these groups do have a doctrine. I like to think that they share common beliefs in the power of compassion and the golden rule.