I am not sure if all these would be consider lesser known but here are my picks:

The Miracles - Renaissance
Billy Griffin debut with The Miracles. The whole album is awesome and "Don't Let It End [[Til You Let It Begin)", "I Didn't Realize The Show Was Over", "What Good Is A Heart Good For" and "I Love You Secretly" are some of my all time favorite songs.

Chuck Jackson - Goin Back to Chuck Jackson
Chuck's second album with Motown and my favorite of the three he recorded during his time with the label. He does an outstanding job through the many cover songs and original material.

The Marvelettes - Sophisticated Soul
I will agree with others on this one. This one contains one of my all time favorite songs written by Ashford and Simpson and sung perfectly by Wanda Rogers: "Destination: Anywhere".

The Temptations - Meet The Temptations
Love hearing the truly unrated Paul Williams on many of the leads.

Gladys Knight & the Pips - All I Need Is Time
Love "I'll Be Here [[When You Get Home)" and "Oh What A Love I Found" plus Gladys' awesome covers of the Staple Singers "Heavy Makes You Happy" and Sly Stone "Thank You [[Falettinme Be Mice Elf Agin)".