I would definitely recommend splurging and going for a haswell i5 for 50 more. Guaranteed no bottlenecks! 600w is pushing it but you will most likely be fine. Also, the custom cooled r9-290's are almost amoung us. If you wait, a huge improvement in Db and cooling would be your reward but hey! Get whatever card you want.
In my humble opinion, I highly recommend getting either a 280X or waiting until the 290 has aftermarket coolers. From what I hear, the 290 can get really hot, and that's not a good thing. Wait for the non-reference coolers, or get the 280X, which will save you some money and be very powerful (it's pretty much a 7950/7970).
If you want a good build for 600 pounds, you could probably get a 280X and a lower wattage PSU like a Corsair CX430 or CX500. They're usually less than $50 if you use a rebate, and you won't get anywhere near them anyway.
Everything seems just fine to me. No reason to wait for aftermarket if you're not gonna overclock as the 290 is built for the heat. Also will the 290 be an XFX or PowerColor? In that case you can if you want flash a 290x bios on it to get 290x performance for free.
The 280X is fine for BF4. I would save some of that money and go with a Haswell. Then you have a much better upgrade path. Seems socket AM3+ is used up.
Depending on the game you will see about a 5 percent difference in that processor to a haswell chip.