Did you read any of those three Carter biographies ("His Very Best: Jimmy Carter, A Life", "President Carter: The White House Years", and "The Outlier: The Life and Presidency of Jimmy Carter") that came out within the last few years? If so, which was your favorite/which do you recommend? I have usually heard Jonathan Atler's is the definitive Carter biography these days.
I still have not gotten around to reading Kai Bird's The Outlier: The Unfinished Presidency of Jimmy Carter (BOOK | KINDLE), but I've been meaning to do so. Kai Bird does great work and his biographies of J. Robert Oppenheimer (American Prometheus -- the basis of Christopher Nolan's next film) about and Robert Ames (The Good Spy) are both must-reads.
I have read the other two books that you mentioned and they are both excellent. I'd agree that Jonathan Alter's book, His Very Best: Jimmy Carter, A Life (BOOK | KINDLE), is the best biography of Carter that I've come across. It's also a true biography that covers Carter's entire life.
Stuart E Eizenstat's President Carter: The White House Years (BOOK | KINDLE) is also very good. While Alter's book might be the definitive biography of Carter's full life, Eizenstat's book is arguably the definitive book on Carter's Presidency. Eizenstat focuses strictly on Carter's 1976 election, single term as President, and unsuccessful bid for reelection in 1980. Eizenstat goes deep inside the Carter White House and spends 1,024 pages covering no more than a five-year period of Carter's political life, so there's a remarkable level of insider knowledge, extensive research and impressive detail in his book.
One other book that I'd suggest checking out if you're interested in Jimmy Carter's time as President is Lawrence Wright's 2014 book, Thirteen Days in September: Carter, Begin, and Sadat at Camp David (BOOK | KINDLE). It's not solely about President Carter, but he's obviously one of the main characters as he hosted Egyptian President Anwar el-Sadat and Israeli Prime Minister Menachem Begin and helped negotiate the historic Camp David Accords. Lawrence Wright is one of my all-time favorite writers and this book is packed with high stakes, tons of drama, and extremely fascinating characters, particularly Sadat. It's also an interesting look at the little-known but highly significant role that First Lady Rosalynn Carter played in helping hold the negotiations together when things got tense between the principals. Like I said, Carter is not the main focus of the book, but it's such an incredible read and it is the story of one of the most important and lasting accomplishments of Carter's Presidency.