Only you can really answer that honestly. I could rattle off a list of things but you would probably say "why would I want that?". Sort of depends on how you use it.
I know the N7 supports standard USB peripherals like keyboards, mice, game controllers (yes, you can literally plug an Xbox 360 controller in, and works out of the box), flash drives, etc. As far as I know, the iPad doesn't have that capability, short of using Bluetooth, which the N7 can do as well.
And I guess there is Flash support (although its unofficial now as Adobe stopped developing Flash for Android) and isn't as much of a killer app that it used to be since HTML5 video is starting to replace it.
You're also not tied to iTunes (or the Google Play Store in the Nexus 7's case). Your Nexus 7 could be completely independent from your PC and Google services if you so chose. Using Google services is recommended but not mandatory. You don't have to use a Google account to even get apps. For example, if you wanted to use the Amazon App Store, you just go to Amazon's web site and download their app. No Google required. As far as I know, you still need iTunes to a lot of things on iDevices. At least, that's how it was when I had an iPod Touch, even when it was jailbroken.
Yeah, this is sort of a broad question, since I'm not 100% sure what the iPad CAN do jailbroken. My knowledge of iDevices goes up to the iPod Touch 2G and iOS 4.