In better dress to trim thee was my mind,
But nought save home-spun cloth, i' th' house I find. (17-18)
Well darn, all she’s got is “home-spun cloth.” It sure sounds like this is a neat little metaphorical description of the all-too-common problem of not being able to find the right words to say something, or “better” words.
In this array, 'mongst vulgars may'st thou roam.
In critic's hands, beware thou dost not come, (19-20)
The speaker implies that the critics will not be very kind to her writing. The speaker’s fears here are similar to the fears we all feel when showing our work to peers, friends, family, and especially teachers.