micro volt signal amplification
The first stage should also apply as much gain as is possible to reduce the impact of self-generated noises in the op-amps. For instance, the ADA4528 has a noise figure of 5.6 nV/\$\sqrt{Hz}\$ and if your 2nd stage also was a 4528 then the noises would add to give about 8 nV/\$\sqrt{Hz}\$. This is when there is no gain in the first stage.

However, if your first stage had a gain of (say) ten then the equivalent noise at the input to the 2nd stage is 10x 5.63 nV/\$\sqrt{Hz}\$.

Noises add as RMS terms do hence they add using \$\sqrt{A^2+B^2}\$

So, get as much amplification into the front-end as you can in order to reduce noise effects.

The ADA4528 is a good choice but beware, at 200 kHz the noise (due to internal switching circuits) is significantly higher. If your bandwidth is much smaller than 200 kHz then you'll be OK.