What does Austen put forth as grounds for good marriage?
In Pride and Prejudice, the best marriages are based on the mutual esteem of the partners. As Mr. Bennet says to Elizabeth when she tells him of her engagement to Mr. Darcy, "I know you could be neither happy nor respectable, unless you truly esteemed your husband."
Elizabeth does esteem and respect Darcy, and he her, suggesting theirs will be a successful marriage. Readers can feel the same assurance about Jane and Mr. Bingley, who also love and respect each other.
But even without mutual esteem, it is possible to have a good marriage in Austen's universe, as in the case with Charlotte Lucas. She finds her husband, Mr. Collins, ridiculous, but she is sensible and prudent enough for the two of them, arranging affairs so the marriage will be bearable. In Austen, good sense and maturity are always more important than grand passionate love to the success of a marriage.
Money is also important in Austen's world: Elizabeth, Charlotte and Jane all make financially advantageous matches. Austen is practical and sees financial security as an important ingredient of a good marriage. For example, the sensible Mrs. Gardiner steers Elizabeth away from an imprudent match with the dashing but penniless Wickham.
Marriages based on fleeting physical passion, such as that of Lydia and Wickham, have far less chance of success in Austen.