Glad you up and running, you must overlay a house curve on the bass as you don't want it flat, add 1-3 dB boost in the bass with the tone controls. Flat measured at listening position will sound bass light.

As to turning it up, the antimode applies VERY conservative headroom compensation - go to the Audio settings and reduce the headroom as it loses you resolution if it's high... the problem is that you keep on having to do this as any change in the curves or parametrics you make result in the antimode overriding your headroom setting and going back to ultra conservative.

Do not worry about or try correct suckouts, they are normally VERY steep and are not that audible - not as audible as peaks.

You can really fine tune the bass, what with the Meridian's controls and the offboard processor; fiddle with tilt as well as all the rest, I have found that tilt also affects the bass, sometimes just changing it snaps it into place or gives it more weight.

Roon/Tidal, SBT, Trinnov ST2 , Twin Devialet D premiers, Vivid Audio Giya G1 Spirits, dedicated and treated room.
Meridian gear: 568.2mm and DSP5000's acting as TV speakers.