I don't know what you mean about "terrible canadian bilingual keyboard" but I just receive the Canadian version and I actually have the keyboard that you can see on this picture http://cdn.liliputing.com/wp-content/uploads/2015/03/c100_01.jpg
The difference is the amount of memory (RAM) the chromebook has. The 4Gb, 16Gb model has 4 gigabytes of RAM and 16 gigabytes hard drive space, and the 2Gb, 16Gb model has 2 gigabytes of RAM and 16 gigabytes hard drive space. The difference will really become how much you use it, the 4Gb model is always going to be faster, but if you just use the chromebook for basic web browsing then the 2Gb will work for you as well.
For me, I use this for work, so the 4 Gb of RAM made more sense.
I'd say it delivers a solid 4-5 hours at full brightness. The only major drawback I see is that the power connector is proprietary and not your standard micro-USB, which severely hinders your charging options or sets you back some monies having to buy their special charger...
Skype yes. Photoshop no. This is not intended for graphics or for Microsoft Windows applications. It is based on the Android operating system. Similar to what you would see on a mobile phone or tablet although it's been modified a little bit for the laptop. You need Internet access to use it properly although it is a bit usable without internet. Ideally used for web surfing and document editing creation management like Google Docs or Microsoft Office (limited versions). A lot of Android applications will work on this device although not all.