Optics is top, tower speaker are top, Sound Bass is quite enough, too. ARC - a dream (Samsung 55Zöller & SKY receiver). Living rooms are 20 square meters.
Who wants more must also spend more (AVR, powered subwoofer etc. A4 is just no RS4, though the A4 certainly not the worst car is ...).
For narrow money use an optimal optical and sound package! Buy!