So you want to get a job. You can specialize in the areas where the most jobs are, or you can do the field that interests you the most and not worry about the job market.
Another way of looking at this, though, is that the most number of jobs are in the most crowded fields, so that in Modern Latin American, for example, you have to beat out 200 other applicants for any given job. Now, obviously, if you are a truly qualified applicant, then your chances are better than .5%, but still...
The second point is that many SLAC jobs do not require extreme specialization. What matters there is not the exact nature of the research, but the ability to teach a variety of courses. The smaller the department, the greater the value of of a generalist. You want to be able to teach beyond your dissertation in any kind of institution.
My colleagues line up approximately like this
Early Modern Peninsular (2)
19th Century Peninsular (1)
Modern Peninsular (2)
Colonial Latin American (1)
19th Century and Modern Latin American (6)