Calling Richland the same generation as Trinity would be like calling Sandy Bridge the same generation as Ivy Bridge; in either case, it's simply not true. Both are small evolutionary steps. And again, assuming FM2 will support Kevari (I haven't seen/heard any solid confirmation of that), socket longevity was never an issue for the OP, which makes the point moot.
And who's to say AMD won't release another chipset by the time they release their Steamroller CPU's and APU's? You know, something with PCI-e 3.0 support? DDR4? Or maybe motherboards will see a price cut by then as well? "Future proofing" is a very futile task with computers since both the tech and their pricing changes so rapidly.
In my personal experience, I got burned by getting the motherboard early. I got a P67 chipset, and Z68 was clearly better offering the best of both P67 & H67, while also offering it's own unique features, while maintaining the same price bracket to boot.