I'll make a couple comments about posting graphs.
It's best to use the standard here at the shack of vertical axis = 45dB-105dB and horizontal axis starting at 15Hz and extending for subs to 200Hz and whatever you like for full range.
With full range measures it doesn't hurt to use 1/3 octave smoothing to reveal the underlying trend of the response that is hidden by comb filtering and to more closely comply with our hearing. Smoothing is not recommended on subwoofer plots though.
It's a bit easier to view waterfalls in the LOG mode rather than LIN mode since that will match the response graph scaling. Then you can move the slider to 1 slice and see the initial response and slowly move to 30 slices and see it ring out.
Hopefully you're not using a Radio Meter for those full range measurements - there not really suitable for that.
Anyway, you're getting some sharp cancellations with your subs and you have a peak around 45Hz-60Hz. Since you have two subs you may be able to use them to support a better response (not that it's too bad now). Try measuring one at a time first to get a feel which one is contributing to any large peaks or dips and them try and get them to work in concert for the smoothest response by moving them around (if that's possible). You may also benefit from equalization with your subs if placement doesn't solve any problems. There's really no treatment that helps at those low frequencies. EQ and placement are your options there.
brucek