The increase in technology with a 70D will be significant
. Everything will improve in a very noticeable way. AF, Low Light Performance, Feature Set and even something as simple as turn-on time. This means that the lenses she already has will likely be able to work better and produce better images
. I would probably wait until the 70D has seen some time with all the lenses before another lens purchase is considered. At that point you'll have a better idea which lenses are winners and which ones might be able to be sold to help fund another lens.
You will probably be able to find some great deals this week on the camera, SD cards, etc.If you decide to get her a 70D, I would highly suggest at least a couple new SD cards that are larger and faster
. The file sizes produced will be larger and the faster fps will also mean more shots are likely to be taken during a given shoot. Avoid eBay deals and be careful on Amazon as well. (I buy most of my cards and stuff on Amazon or NewEgg, just read the reviews.) UHS-1/600X should be fast enough. Get at least 32GB and maybe even 64GB if video will be a common use. There are many good brands but I've had good luck with Transcend, PixelFast, WinTec, etc. Sandisk and Lexar are the flagship brands and the prices reflect that. Since I'm an IT guy, I look at this stuff a little differently than most others. Regardless of brand or seller, I simply test all my cards after I get them to make sure there are no bad sectors.http://sosfakeflash.wordpress.com/2008/09/02/h2testw-14-gold-standard-in-detecting-usb-counterfeit-drives/Extra batteries are also a good idea
. There are two sides to the battery debate on this forum, OEM and Aftermarket. I'm afraid I fall on the aftermarket side. I've never had a problem other than Canon's recent firmware follies where the camera can sometimes nag you if you aren't using a genuine Canon OEM battery. Personally, I've used the Wasabi batteries (link below) and they've worked fine the hundreds of times I've relied on them so far.http://www.amazon.com/gp/product/B0049XGNKK/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
Keep us posted on how things turn out! It's always fun to get a new camera and even more fun to give one!