It's amazing how simple a lith developer can be. My problem with the more simple formula (hydroquinone, sodium sulfite, potassium bromide & alkali) was that they had no tray life. Sometimes 5 8x10 prints was all I would be able to pull from a litre or two. Considering the first one was usually ordinary, that wasn't so great. If you seperate the alkali (like in ID-13), you get a pretty stable developer in terms of shelf life.
Boric acid is used in lith developer formula. It might be a good choice to achieve the ph you're after. It also has benefit of acting as a ph buffer in small amounts; or so a chemist told me. There's mention of it in this thread:
I'm no chemist, for the record!
Insofar as ID-13 (and the other similar formula), it works. I usually found diluting it in the ballpark of 1:1:9 was ok for lith printing. If you use a stronger concentration, the sodium sulfite levels are too high and you won't get infectious developer. Colour wise, and dmax wise, it's nothing special. You can definitely lith print with it, but when you compare it to a commerical product like LD20 or Moersch... well... it's rubbish.