Please stick with "he".
I agree that it's imperfect, but inelegance matters.

And I tried using "she" as the default for a while, but people kept getting confused because they weren't expecting it, and trying to figure out where I'd mentioned a female.

Yes - and this is the problem. People shouldn't think that a female pronoun is weird... just because it's female. ...and you shouldn't be afraid of using it just because people might think it unusual and get confused for all of two seconds.

If you, and the other more post-prolific and respected members of the community used female pronouns more frequently (ie on average: as often as male ones) then eventually it would become commonplace and people would eventually figure it out.... that it's just a pronoun. Just like the other one... only female.

Alternatively, a lot of people these days are just fine with "they"/"them".

Yes we have twisted English into a way it never was used before and it sounds weird to those of us "brought up better"... but this is what happens with languages.

Especially English.

I'm sure I could go through your last post and pick out half a dozen things that, in their time, were considered weird and "not correct English"... until everyone that used to hate them died off and it became just part of common language.

AFAICT, it's currently the most widely-accepted gender-neutral pronoun. You can fight the tide... or not. :)

A lot of people object to "he or she" on grounds of euphony; but clarity of meaning should always take priority in our considerations over sound. The fact is that "he or she" is what we actually mean.

Granted, like any phrase, it is inelegant in certain contexts, and can become tiresome if repeated. So one has to use workarounds. Luckily, "they" (always perfectly acceptable in spoken conversation) is also available for judicious written use.

"the most important reason to argue with someone is to change his or her mind" sounds just fine. ("Their" could also be substituted.)

"Either a person has enough of the rationalist virtues to overcome it, or he or she doesn't" is bad, mainly because of the "or" preceding "he or she". "He/she doesn't" is better, but "they don't" is probably the best (certainly in a comment; maybe a post should be more formal?).

Invented pronouns are just too strange and should be avoided.

Landsburg:

I am therefore confident that no attentive reader will mistake my repeated use of the generic pronouns "he," "him," and "his" for the exclusively masculine pronouns with the same spellings and pronunciations.

Regarding being a grammar purist, it should be noted that being offended at using 'them' as a singular indefinite is a relatively recent trend.

'ze' and 've' are aesthetically unpleasing, but using them more is likely the only way they would become less so. You won't find me doing it anytime soon though.

It should be noted that until recently, 'man' was gender-neutral in English. John Stuart Mill found himself just on the cusp of that, and tried to argue for women's suffrage in England on the basis that the law referred to 'man' and so included women. (he lost). Common archaic equivalents to todays' 'man' and 'woman' are 'were' and 'wif', where 'man' meant the whole species (though commonly that only considered males).

'She' isn't that confusing, and radical feminism isn't the pernicious beast it was in the 90's, so it seems like 'she' is the best bet for a gender-neutral personal pronoun.

Personally, I prefer to invent a subject for such a thought experiment and then use the appropriate pronoun for the person's gender - which is what you did here with Theo.

Hofstadter has made an excellent argument on this topic called "A Person Paper on Purity in Language".

Iain Banks, in "Player of Games", also expressed this sentiment pretty well:

"Marain, the Culture's quintessentially wonderful language (so the Culture will tell you), has, as any schoolkid knows, one personal pronoun to cover females, males, in-betweens, neuters, children, drones, Minds, other sentient machines, and every life-form capable of scraping together anything remotely resembling a nervous system and the rudiments of language (or a good excuse for not having either). Naturally, there are ways of specifying a person's sex in Marain, but they're not used in everyday conversation; in the archetypal language-as-moral-weapon-and-proud-of-it, the message is that it's brains that matter, kids; gonads are hardly worth making a distinction over."

My preferred sex-neutral pronoun is "they".

Instead of gender neutrality, try to go for gender balance? I use alternate "he" or "she", and occasionally, semi-intentionally contradict myself [for example, in a talk about Bayes, I explained what I meant by "overconfidence" with an example -- the specific numeric example used a name, Sally, and the general definition used "he". For underconfidence, I used "Barry" and "she" respectively". I believe Eliezer used to physically flip a coin for he vs. she.

I think I remember reading that the plural used to be conventional grammar and was then deliberately suppressed in favor of "he".

I use the plural. It grows on you surprisingly quickly and isn't at all obtrusive. Anyone who doesn't already have the info stored "Oh, Eliezer uses the plural" after reading my writings for months is a case in point thereof.

Thanks for the thoughtful response. I do appreciate that this inevitably opens up a can of worms, and that no solution is really ideal.

I agree that "he or she" awkward in many, if not most situations. For whatever it's worth, my preferred solution is to use the plural (they/them/their) in any situation where it's unambiguous enough to function effectively, and to otherwise use she/her. If people are confused by feminine pronouns... well, that kind of just illustrates the problem, and making them think about that at least serves some sort of purpose.

For myself, I use the generic feminine wherever possible in writing, but that's just me. In natural speech, I use they, like everyone else.