For sure there are better sound-proofing cases. Case market, especially silence-focused moved forward and use different, better solutions to keep things quiet. Let's start with example, duel of P183 with first Fractal Desing Define case as representative of new wave:
https://pclab.pl/art40680-9.html
It's polish, but you don't have a choice, so need to use translator or believe me :> They tested P183 and R2 with default set of fans, but also populating every fan slot with the same Noctua's fans. It can seem not fair, that R2 got more Noctuas, but it will lead us to answer to your question.
It can be hard to translate, what's on the picture, so I will do it for you:
What you need to look at in terms of your question are two measurements: ,,Antec P183 NF-P12 700 obr/min", what means ,,Antec P183 with NF-P12 fans running 700 rpm" and ,,Define R2 NF-P12 700 obr/min, boczny otwór zasłonięty", which means ,,Define R2 with NF-P12 fans running 700 rpm, side panel hole closed". What's the most important, both records differ with amount of Noctua's fans. Antec has them four, R2 six. More sources of the same noise increases overall noise. Comparing noise and temperatures measurements leads us to conclusions - R2 can handle more noise still being a little quieter, but it also then outperforms Antec in terms of temperatures, so give you bigger headroom to make computer even quieter by dicreasing the speed of components fans. This aspect wasn't included in test's procedure, because they used on CPU and GPU coolers additional NF-P12 fans running constant 700 rpm, so both cases were dealing with the same noise of components.
This duel is example of how things changed with the time. P183 - if I remember well - represents times, when Antec was sound-proofing its cases by placing layer of plastic between two layers of metal. Fractal experimented with three types of foam and established standard of construction and one particular sound-deadening material, which Antec and other brands followed, so it's rather superior.
Still thinking about USB problems or just want to buy new, better case? It will be better in any way, not only sound-proofing, but also ease of maintenance and build, possibly dust filtration or more modern, maybe richer amount of USB ports. If secound option, only the matter what you need the place for. I mean mostly some HDD collection, EATX board or 5,25 devices. All lead us to bigger cases, so don't count to get something much smaller than P183. If your needs are small enough, we can go with something more compact. Advantage of bigger cases is more place for big CPU and GPU coolers - the quietest ones. The size of them tends to increase, so I wouldn't go with compact cases, if you want to use new one for years and few upgrades.