If we are talking FHD you will be fine with a r9 270 or a r7 265 but the price difference is small so go for the r9 270. Of course you must be sure your system can handle this card, post your cpu to see if there are any bottlenecking issues, and your psu to make sure it is sufficient.
Yeah, no need to overclock for Planetside 2. One thing though, get the k-version of the CPU, that way you can overclock the CPU whenever you feel like you need more power.
Yeah, but you only need to get a cooler when you decide to overclock. Of course if you're sure you won't overclock, you might as well get a cheaper H97 motherboard, no need for an expensive Z97.