Noelpastor,
I found the bass response from the Continuum to be well balanced with good resolution. On the Eggleston Andra IIs I had to concentrate a great deal on speaker placement and room treatment to keep the bass under control - it became overpowering when the speakers were too close together or too near the front wall. When I got the speakers properly aligned, the bass seemed to be well in keeping with the frequency response of the rest of the speaker.
The Mementos don't have much bass response below about 35- 40hz, but the Continuum did a very good job of delivering and controlling what bass response was available.
As to whether the bass response improved during the break-in period, It did improve, but not so much as the other characteristics of the amp - transparency, refinement, resolution, soundstaging etc. When I first started using the Continuum, I was still messing around with Eggleston speaker placement and, as stated earlier, the bass response was too full and I had to tone it down through speaker positioning and the use of tube traps.
I do think that breaking the amp in at low volume will take a great deal longer than doing so at normal listening levels (or higher). I would suggest that you turn the thing up a bit and enjoy. . . . .