The MW is absorbing at least two dwarf galaxies at the present time. But a more massive one would have indeed produced distortion or warpage. These are numerous.
I assume that if the MW did absorb this galaxy to a large extent, then our orbit would move inward a bit, assuming most of the absorption would be within our orbit.
If the prior galaxy were significantly older, then I suppose gas collisions would contain higher metal levels than would be expected, but this is just a guess and I think it would be really hard to guess the composition of the long gone galaxy.
Nevertheless, new star formation is inevitable as gas clouds impact one another, thus spewing more life-oriented elements. It's a wild guess if this made a difference for our Solar system, I suppose.