Further Consideration on my BX Psionics System

The other day, via a Google+ thread, Matthew Skail asked why I was opting for a random psionic strength point (PSP) gain with leveling, and that the other classes don't do that. For those who haven't been keeping up with the earlier posts, I was treating PSP gain like hit dice, with the die type rolled based on the character's Wisdom score (a reminder/note that, in my system, Intelligence is the defensive psionic attribute, and Wisdom is the offensive one). Honestly, I was originally trying to capture the randomness of psionics in Oe/1e. But, upon consideration of MS's comment, I realized he's right. Thieves don't, upon reaching a new level, randomly determined their increased chance to move silently. So I went back to the drawing board... BUT, I did so with another key point in mind — I wanted to make sure that as the mystic gains levels and PSPs, the DM can easily figure out what kind/strength of psionic creatures to pit him/her against. The following chart is where I've landed.

The basic formula for PSPs gained at each level is 10+(levelx2).

The PSP bonus at each level from WIS is based on the following:
WIS 13-15 = +2 PSPs/level
WIS 16-17 = +4 PSPs/level
WIS 18 = +6 PSPs/level

This puts a 7th-8th level PC on relative par with a shedu (9+9 HD, 70-100 PSPs, performs at the 9th level of mastery).

This puts an 8th or 9th level PC with a WIS of 18 on a relative par with a psionically "low-end" mind flayer (8+4 HD, 241-340 PSPs, performs at the 7th level of mastery).

As always, I'm sure there will be more to come.