These Protestants are not sola scriptura. They are likely to reject significant stories in the Bible, like Noah and the Flood and God ordering Saul to slaughter every last Amalekite. They are skeptical of certain New Testament miracles, such as Jesus turning a few loaves and fishes into enough food to feed 5000 and Christ putting demons in pigs. They are likely to emphasize reason, usually have a deep faith in God, but tend to think of strict-believing Christians, Catholics or Protestants, as unwittingly embracing superstitions.
For example, these Protestants honor Mary but are alienated by what many view as the Mary cult - veneration, Immaculate Conception, Assumption, sinless life, etc. They certainly don't believe in transubstantiation but treasure communion as a fellowship meal in loving memory of Christ. They don't pray to saints and consider many of these as hold-overs from paganism, and they feel that stories of saints levitating, bilocating and such are fantasies. Their main emphasis is likely to be on Christ's two great commandments: love God and love one another. When it comes to heaven, they probably believe in an afterlife but confess little or no knowledge of what it will be like. Thye are sure that God's mercy will permit most people of whatever faith to get there.
Most 'big tent' Christians are very tolerant, even friendly, toward other faiths, except those (like Muslim extremists) who embrace a form of their religion that is hostile toward them. They value freedom of thought, differ amiably among one another, participate in Bible studies where all sorts of views are expressed without animus, like to learn of other religions and appreciate the wisdom they find in other scriptures. They are Christians in that they seek to follow Christ, but they appreciate the good they find elsewhere.
Much more to say, but that's a start. These folks are numerous in such denominations as Methodists, Episcopalians, United Church of Christ, Presbyterians, etc. They switch denominations easily if they move and find that another mainline denominational church offers a better Sunday School, better preaching, a more convenient location, etc. In places like Canada and Australia and parts of India several of these denominations have merged - e. g., Canada = United Church of Canada. The main noticeable difference at worship might be liturgy - heavier among Episcopalians, less among Methodists, least perhaps in the American Baptost Convention churches, a 'big tent' branch of the Baptists.
Most of these churches have attracted Catholics who like their freedom of thought and their lack of any central theological or tight ecclesiastical authority. At the same time, they are losing membership to the more evangelical churches or to 'no church'.
As you can tell, I am attracted to this form of Protestantism, though I have an ecumenical (Catholic/Protestant) family background and often find myself conflicted.
May God bless good people of every faith.