I've noticed some biographies of saints are very short. What makes the Shri Sai Satcharita a more suitable choice for someone wanting to do an in-depth study or group reading?

The preface in Chapter 0 directly addresses this concern. It notes that while many prose and poetic biographies of Gurus exist, they are often not comprehensive or detailed enough for dedicated Parayans or Saptahs, sometimes being only a few pages long. The Shri Sai Satcharita, written by Annasaheb Dabholkar, is specifically praised as a 'recent, sweet, inspirational, and grace-filled biography.' Chapter 0 emphasizes that it is a detailed and comprehensive work, making it highly suitable for Parayans. This depth allows a community of devotees to thoroughly engage with the life and teachings of Shri Sai Baba Maharaj in a way that shorter texts do not permit.