Probably tax and related areas like ERISA, trusts and estates, and perhaps real estate.
By all means take QOL into consideration when choosing a practice group, but you should really focus on what you'd like to do. For the most part, the differences in hours are probably not hugely significant. Also keep in mind that in most firms, more QOL practice areas like trusts and estates usually don't have that many attorneys, and turnover is also probably lower. So if you tell a firm you only want trusts and estates, or give that impressionn without coming out and saying it, the firm might not call you back simply b/c they don't anticipate needing anyone in that dept.