I don't have any experience booking with points, but based on what I know, there is absolutely no down-side to you booking when the flights are released and getting a subsequent credit if the points/fares drop. SWA makes it so easy to do this!
As far as fares go, I've seen just about everything! Sometimes the best fares are available when the schedule opens and sometimes the opening fares are high. Since I pay cash, I watch the fares for a few weeks or months prior to my "opening day" to determine what a good fare is. If I see a fare that is close to that price when the schedule opens, I book. If not, I wait. I always book my departing and returning flights separately so I can change the flights easier if fares go down.
Most recently, I did not book on opening day because it was too close to the holidays and I didn't want to pay for the tickets yet. Much to my dismay, I watched the fares climb (double in price) over the next several weeks. Then magically, on a Saturday morning, the fares dropped lower than I'd ever seen them... and I pounced! So you never really know when the best fares will come out... you just have to keep watching... and get lucky!