After I got that out of my system, I searched the boards, and it turns out it's not even hard to read ADE PDFs on an ipad. You just need Textr. Since Textr has been around for 2 years, it's possible that my fellow bloggers using NetGalley already know this, but with thanks to those who already posted on this topic, I'm offering this short how-to for other ipad users:
You need to create an Adobe ID if you don't already have one.
Then install ADE on another computer (not your ipad, although my ibook plays nice).
Download the Textr app to your ipad. This will prompt you to create a Textr account.
In the Textr app, go to settings and enter your Adobe ID.
Download your NetGalley or other ebook to the computer where you installed ADE and open the ebook in ADE.
On the same computer, go to the Textr website and login.
Once you're logged in, click on My Books. Click on upload. Navigate to the Digital Editions folder on your computer (mine's in my documents). Select the PDF you want to read on your ipad and upload.
Open Textr on your ipad and your book will be there!
I'm currently reading a NetGalley of a GN, and there's a little bit of lag before the images appear clearly, but it's readable, and I am victorious!