To me - it is in a good spot. I am not likely to use the laser with regularity. I don't like some lasers, such as crimson trace lasers, because I feel like i have to adjust my grip if they are "on" (the master switch is on) but I don't want to make use of the laser at a particular time.
I don't want a pressure switch on the sides - where I normally hold the weapon - but would have to twist my grip to NOT have it on.
With the way mine is set up, it is on the edge of that front portion. I just extend the first finger on my left hand if I want to use the laser. I like it that way. I have no intentions to short barrel the PS90. So, there are no "bad habits" to develop that could lead to anything else.