I think the ar5’s would generally be better, but if you have to repair them it might not be worth it. IMO, it’s worth having matching front and back speakers, at least within the same line. And even if they’re lower in the list, don’t forget to eventually use good surround speakers. Modern tracks are very busy, and sound travels throughout so IMO, use good surrounds too. But first things first..
HSU offers great value, but there’s also Rythmik and monoprice/monolith, and as you already mentioned, SVS. The room is tiny so maybe a pair of rsl speedwoofers for 800 bucks. Two would go a long way to combat being in a square room too, and they’re smallish.
Also, RSL has exemplary customer service.