I have at least 8 different translations plus books with commentary on some but not all of the Sutras. I also recently signed up for Georg Feurstein's 500 hour course on the Sutras. And I teach the Yoga Sutras for yoga teacher training both 200 and 500 hour training at SMC Marin. I don't have one favorite. I will list the ones I like and why.
"Raja-Yoga" by Swami Vivekananda is probably the deepest teaching as he was a realized master. The book consists of notes from his lectures and classes from around the turn of the last century. For many Westerners it is a little bit difficult to jump right into his teachings - and the style of the writing. But if you can, it is very deep and accurate.
"How to Know God The Yoga Aphorisms of Patanjali" by Isherwood and Swami Prabhavananda give a more updated and easier read blending Vivekananda's teaching with the authors’ own philosophy.
For a comprehensive book that refers to the insights from early traditional commentaries I like the rather thick book, "The Yoga Sutras of Patanjali" by Edwin Bryant.
One I recently picked up is "The Essential Yoga Sutra" by Roach and McNally. These authors have picked up on some of the more esoteric and subtle meanings/interpretations of the Sutras that I find are often lacking in modern translations (even those written by yoga teachers from India)
Finally I recommend the "Art and Science of Raja Yoga" by Swami Kriyananda. We use this as a text book for teacher training at both schools of yoga where I teach. As the title suggests it is about much more than the Yoga Sutras, but I find that the sections on the Sutras are very straight forward and helps the students to have a context for deeper study of the Sutras. Also many other concepts such as the gunas and other yogic principals and Sanskrit terms are covered and it makes it much easier to understand and interpret the Sutras.
I don't think you need to know a lot of Sanskrit to study the Sutras. To really know them you need to meditate and practice the teachings outlined in the Sutras - otherwise one's understanding remains at the intellectual level.