I believe that Neera's moral character and the unpredicable quality of her magical abilities have been conflated in her development so that her alignment has been presented as Chaotic Neutral when in fact it is much closer to Chaotic Good. Some people on the forums have argued that she is too 'friendly' to be neutral, and this has been rebuffed by others, who suggest that even a truly diabolical character can be friendly when it is in their interest to be so. I agree with the latter, and do not suppose that Neera's friendliness has anything to do with her (in my opinion) miscast alignment.
The character creation screen reads: "Chaotic good characters are strong individualists marked by a streak of kindness and benevolence. They believe in all the virtues of goodness and right, but they have little use for people who "try to push folk around and tell them what to do." Their actions are guided by their own moral compass which, although good, may not always be in perfect agreement with the rest of society. A brave frontiersman forever moving on as settlers follow in his wake is an example of a chaotic good character."
This seems to describe Neera perfectly. In her in-game biography, she "seems to fear the harm [her wild magic] might cause." A Chaotic Neutral character, on the other hand, will "cheerfully and for no apparent purpose gamble away everything they have on the roll of a single die." If Neera were truly Chaotic Neutral, therefore, she would not fear the harm her wild magic occassionally causes. Rather, it is on account of her intention to do good that she harbours such fears. (And isn't alignment all about intention?) Such intentions are evidenced when Neera uses her last teleportation talisman to save a child in Athkatla, and thereby endangers her own life. The fact that she has created a wild mage refuge suggests, more than anything, that "her actions are guided by [her] own moral compass which, although good, may not always be in perfect agreement with the rest of society." Moreover, one could interpret the creation of such a refuge as the act of "a brave frontiersman" with a sense of her own moral compass. She is also a "strong individualist," evidenced by the fact that her greatest fear is "being taken by a crazy wizard who wants to tear you apart for what you are. Not even who I am. WHAT I am." Thus she values her individuality, and takes pride in her magic, but uses it out of a desire to do good. Indeed, she resents being judged not by her character ("who I am," a moral judgement), but by the quality of her magic ("WHAT I am," a non-moral judgement). Perhaps the developers- for whom my respect is nonetheless unwavering- did likewise? For, by contrast, a Chaotic Neutral character possesses no moral compass whatsoever. It is not of their concern whether their actions are good, evil or otherwise.
The only real argument for Neera being Chaotic Neutral, in my opinion, is that she continues to utilize her magic despite its unpredictable consequences. Perhaps a truly good character would leave magical pursuits aside and retire to the country? Yet here, you might recall a dialogue between Neera and Aerie wherein Aerie (Lawful Good) admits that she doubts that she would be able to continue using magic if it were as unpredictable as Neera's. However, Aerie says that she admires Neera's "nerve," which suggests her reluctance to be due to nervousness rather than a moral qualm.
Finally, from the character creation screen, "Chaotic neutral characters believe that there is no order to anything, including their own actions." Note the use of the term 'belief' - whilst there is no order to Neera's magic, this does not impinge upon her underlying intention for good to prevail. So that's my argument, in a nutshell (or was it on a lengthly, elaborate parchment?).
If you've any further thoughts, or counter-arguments of your own, do let me know!