It seems like the damping loops are OK for the SRs.  Attached are screenshots comparing each of them to the corresponding PRC optic. I didn't adjust anything on SR2 or SR3, on SRM I  turned off FM1 on L, to match the configuration of the PRM damping loops. I also increased the pitch gain from -2 to -3, since there was more pitch motion on the SRM, the resulting spectra are in the screenshots below. 

SR3 T+V have extra noise at around 13.6 Hz and 16.25 Hz respectively.  This is there with damping on and off, and there are no resonances predicted by the model at these frequencies.  Jeff suggests that these could be HEPI resonances. 

To do this, We had to turn on some ISI loops on HAM5.  To do that, Jamie had to edit the guardian so that now we can request ISOLATED_ROBUST.  Hugh also had to reset the CPS targets.

Based on the top stage osems, it seems like the motion of the SR cavity should be comparable to the motion of the PRC, so large motion of the optics shouldn't be an impediment to locking the SRC anymore now that HAM5 has some form of isolation.