Welcome Funky to the Nexus line of devices!
I have a Nexus 7 and have rooted it, modded it, flashed it upside down and 7 ways north of Sunday, mauled the OS requiring a nandroid backup and it's incredibly robust to handle it all.
You are going to have a ton of fun with it, there are so many readily available tools that make it easy as all hell.
The N7 screen glass is made by Corning, but it is not
Gorilla Glass. It can and will scratch under abuse, get and install a quality screen protector.
I use Tech Armor brand protectors available from Amazon, they have a matte finish so glare isn't an issue and the one time I dropped it on its face (last week about a year since I got it Christmas 12) I picked it up and it had some serious scratches in the protector.
I was extremely relieved when I removed the protector to replace it, every single nick and scratch went with the film when I peeled it off the screen. I just ordered another pack of 3 of the same brand.
The Grouper N7 has a large battery, you need a charger and cable that is robust enough to handle the extra power the N7 or any similar larger tablet requires. The N7 comes with a very high quality Asus cable and wall charger that puts out 2 amps, it needs every bit of that to recharge especially when it is severely discharged.
You will never fully charge the N7 connected to a common USB port of a computer or typical android phone charger, the power provided will just about provide the power the N7 needs to function without even charging the battery. If your N7 didnt come with the factory charger than make sure you buy the factory charger or one with a solid 2amp output.
I actually find a lot of the chargers and cables that come with premium HTC devices charge the N7 very well, pay attention to the output specs.
Normally the shorter the cable the better (typically they are 3 feet), I have bought the Amazon essentials gold plated 6 foot cable and tested it with my Charger Doctor, it is a good brand to buy if you have the choice.
Anytime you start to root and mod the device you should be using the Asus factory cable or a very high quality replacement, the most common issue people have with root, rom, and general flashing/mod work is solved when they try a "different" hence better quality cable.
You should always have your device of any maker plugged directly into a computer and not a USB hub with 5 other things plugged into it, I'm sure you already know that.
You are going to want a "On The Go" (OTG) cable right away if you dont have one -
Amazon.co.uk: otg cable
The Nexus 7 has full USB host support, using the USB OTG cable that changes the Nexus 7 micro USB to a full size USB port you can do so many things.
Having a OTG cable will allow you to fully flash/restore/backup using a single USB thumb drive for all the files.
I highly suggest you buy one with a thinner more flexible cable as it will not stress the micro USB port on the Nexus 7.
A must have for the Nexus 7 is Wug's Nexus Root Toolkit, It makes rooting, tooling, and managing your nexus utterly fool proof.
Nexus Root Toolkit v1.8.0 | WugFresh
Make sure you set your correct device in Wug's and it's a proven reliable tool.
Using Wug's you can restore a factory image, root the device, and so much more awesomesauce it is impossible to list.
Install Wug's, follow the driver install, set your device properly and away you go. Everything else is simply a click away.
You can also dual boot your Nexus 7 where you run the stable stock version of android 4.4 but can instantly reboot the device using multirom and boot into a totally separate ROM like Cyanogen for testing.
Multirom - [MOD][DEC 24] MultiROM v19 - xda-developers
I'll be here for any question or concern you have no matter how daft or minor you may think it.. fire them off at any time, if I have the answer I will gladly provide it.