I have mileage accounts with AA,BA, DL, LH, US, UA, and LX(Swiss)

I'm flying CO codeshare VS UC IAD-LHR.

Most of my flying is IAD-Europe, and most of my miles are with LH. CO does not fly direct to Europe from WAS, so the idea of IAD-EWR-hub-final destination is not appealing.

Where should I put these miles. Should I open either a CO, or a NW account? If NW, do they count for status on NW?