Seems like dual subs is the preferred route. I had infinity ps10, it was a gift from my wife when we were dating
Wow! You’re in for a surprise! IMO, if you’re the only one who cares about the HT, but the single best sub you can afford now, and plan a second one as quickly as you can. Multiple subs are basically a necessity when dealing with multiple seats, and especially multiple rows. But you only care about one seat, and have some freedom in placement, just get a great one now, upgrade the LCR and worry about the second sub and surrounds later. Basically any current quality sub will be an improvement over the infinity which could easily be moved to the garage, or BR or office etc.
I would personally go beyond the 1000 series in SVS’s lineup though. Without considering any connected rooms, you’re at about 3000cuft. So I would at least set into the 2000 series.
Didn’t see any ultra towers but found the prime pinnacles at 700/800ea in ash, or piano gloss.
1400 towers(+700 if using 3rd as center)
Or 349 for the prime center.
700 pc2000.
If you really want the ultras,
$2k a pair
$700 for sub
349 for prime center(voiced to match ultras) just barely over budget.
I’m just spit balling here but you get the idea.