I would say that the reason setting 5 isn't used often is because the hymns that replace the canticle parts of the liturgy are not commonly known by many parishioners.
Setting 1 is based on the ancient liturgy of the Church. It's very similar to the RC Mass I remember as a child. The tones for much of the service are, I believe, from Gregorian chant. It was included in Lutheran Worship as "Divine Service II First setting".
Setting 2 is the same liturgy but with a different musical setting. I'm not sure of of the origin of the setting, but it could have been developed for the Lutheran Book of Worship (LBW). It was also included in Lutheran Worship (LW) as "Divine Service II second setting".
Setting 3 is also known as "Page 15" from The Lutheran Hymnal (TLH). It was also the communion service in the old Evangelical Lutheran Hymn Book from the early part of the 20th century (the year 1912 sticks in my head). It has its roots in Anglican worship and may have been adapted for Lutheran use when the change to English language worship was made.
Setting 4 was developed for the Hymnal Supplement '98. The LSB version is slightly different in a couple places due to copyright issues with the Lutheran Service Builder (electronic edition of LSB).
Does that answer your questions?