Andreas-
Thanks for your response, it was quite informative. Unfortunately the LT6078 takes a maximum 5.5V single supply, while I have +/-6V supplies. I agree that lower offset voltage would be desirable, and while I prefer to design based on worst-case values (as you have done with the 300 uV figure), the distribution on page 6 of the AD8667 datasheet paints a nicer picture. Current noise isn't something I'd put much thought towards, but it makes sense that it would be important. As for bias current, this is a battery powered device generating a maximum of 250 mW, 90% of which is in some front panel LEDs. Temperature inside should never get above say, 30 or 35 °C. Once again, I'd prefer to design based on worst-case values, but I'm certain I won't be getting anywhere near the 85 °C mark where 45 pA max Ibias was measured. With respect to high frequency noise, there is no such source inside the enclosure, and the chassis will be die cast aluminum. That said, I hadn't thought of opening the ring in that manner, and I may do so anyway.
Thanks again for your input!