I think if you start with either the DA*50-135 or FA77 it will give you clarity on where you need to go from there. Save the money for the other lens(es) for a few weeks or a couple of months, until after you've tried one of these. Then you'll know what to spend it on. Compare FA77 photos to those from the DA70 and see which one is
really what you're looking for. There's no question either the DA*50-135 or FA77 makes a great portrait lens. I think you'll be very happy with the images your K-30 creates using either one of these.
The A100/2.8 (non-macro) got me started, and then when I got the FA77 it changed my whole perspective on what I wanted/was looking for photographically.
And no, I don't think any of the lenses you mentioned are overboard. The DA*55 is a fantastic lens. As you've probably already discovered, the other Pentax AF 50mm lenses can't even compare to its performance at f/1.6. The only other lens I've used that's this good at f/1.6 is the FA*85. This is the mark of a good lens - near optimal performance when stopped down only 1/3-2/3 stop. The other two lenses that can compete in this respect are the FA77 and FA31 - both great wide-open at f/1.8, and both producing smooth backgrounds. And the DA*50-135 performs very well at f/3.2. This is why I think either the FA77 or DA*50-135 is the place to start.
Be aware that the DA*55 is probably the sharpest of all these lenses near wide-open, but the bokeh ranges from fantastic to noticeably harsh or distracting, depending on the background. Take a look here:
PENTAX : Select a PENTAX interchangeable lens camera or a lens model