Since your focus mainly on video/home theater and overspending on hobbies is a very valid concern, I highly recommend you to look closely at above mentioned Ascend. CMT-340SE Center will be a vast improvement in dynamics and sound quality over BA's VRC. VRC is rated down to 70hz -3db - which means it actually starts to lose some of the power to play lower frequencies even higher than 70hz. I don't have a frequency chart, but this isn't an unreasonable assumption. Given that the human's voice range is 85-180hz, you could see how your current center would struggle to faithfully playback 85hz accurately (and at sufficient level) and could explain why you needed to raise the center channel +8. CMT-340 has optional stands which convert it to look like a tower speaker.
As for subs: My personal preference would be with HSU - VTF-3Mk2 is a great value, also VTF-15m2 for not much more is worth considering if you have sufficient space for it. So my advice - replace Front speakers and Sub - Keep existing speakers for surrounds.