These are concerns from audiophiles who care more about sound than they do the music. How sad that sound has become more important than the art you're presented with.
Who cares what chair you use. Be comfortable and enjoy.
Moving your chair can help nullify room bass reinforcement issues.
If you do this, your system will sound better and, dare I say, increase your "enjoyment" of music.
I thought that this was why we buy this gear. Read connecting more with the "art".