Recently I read a fic that was, most of the time, pretty good. I mean, nothing spectacular, but enough to make me happy before work. Some of it, though, made me cringe. Not enough to hit the back button, but enough to make me go "oh author."
A few typos I can overlook. But when you're misspelling characters' names? Come on. And the dialogue was sort of stilted at times. Okay, maybe it bothered me more than I thought.
So, here's my question: How do you tell someone nicely that her story is good but she could really use a beta? Especially if you don't want to be roped into it yourself.
A Little Picky (But Only A Little)
You have certainly hit upon a conundrum. Recently, as I am certain readers of metafandom can attest, the matter has received much attention, especially with regards to gift fics. Although that isn't the case in your example, Picky, I believe that looking at the current debate can show just how many different opinions exist across the breadth of fandom! There are those who believe that constructive criticsm given after the fact is less than helpful; there are even those who don't feel confident choosing among the many methods available to contact an author. Is a private message too intimidating? Is an email too stalkery? Is a comment too publicly shameful? When such questions of medium and message can't be decided on, weaving one's way through the pitfalls in giving this kind of feedback can be especially dangerous.
On the matter of typos or uncapitalized names, it would seem that most authors could only benefit from making small changes that could increase the quality of their fic. Mentioning these, especially in the context of a largely positive comment, is generally held as a reasonable thing to do.
However, suggesting that a beta might be a necessary step while evading the spirit of volunteerism is truly a delicate line to walk! Picky, I have been there before, and I sympathize. The result was indeed offering to beta a story myself; fortunately, I had the entirely bracing experience of seeing the writer improve significantly over the course of a few drafts. It was pretty gratifying to see. That experience is not one to be missed!
When you don't have the time or inclination to offer your own beta services, though, the precipice narrows! How do you wish to be perceived by those who might read your comment? Suggesting a beta in an open comment could summarily place you in the ranks of the Cult of Mean, no matter how well-intentioned you are. There are some who find those ranks to be quite comfortable, and embrace the label. Others would be less sanguine. A private message or email might leave you without the response you hoped for: the writer might dismiss you, or simply never reply.
But remember, Picky, that your suggestion, however phrased and however delivered, can be only that: a suggestion. The author has every right to post stories with uncapitalized names and call herself the astral plane reincarnation of e. e. cummings if she should so wish! In this case, you might well have to learn to live with the fact that someone is Wrong On The Internet, a terrible bind. After you've offered your advice, there is really nothing more you can do, short of taking up the beta's reins yourself.
If you can make clear that you are a true admirer of the writer's work and believe wholeheartedly in her ability to improve, and you can communicate that message, then it is worth doing. If, however, you can only nitpick and you would find no satisfaction if you were ignored, then it is probably the better part of valour to leave well enough alone.
May your decision be the right one!