I'm confused. If I read this right, you are saying that you have become accustomed to an inaccurate sub in one system, then, having acquired a more accurate system, want to modify it so that it is ...........less accurate?
And you think an SVS sub will do that... how?
The Seismic 10 looks to be a great sub and the rest of your components are all quality - it seems to me that retraining your ears to recognize well balanced bass is the next order of business. If you only play music on your HT system for a while and still miss the bloated bass – try increasing the gain on the sub, if that doesn’t work, get an eq and jack-up whichever frequencies you need to achieve the same sound.