The Parasound JC3+ would probably be a good choice and a Rega Planar 8 with Apheta 3 cartridge for your system.
As for the goal of "exceeding the capabilities of the rest of the system," I would caution against thinking of analog that way. Vinyl rarely wins on absolute resolution, noise floor, or dynamic range compared to a good digital source, or if it does your will need to spend a lot more money. Then there is the cost of each vinyl record and cleaning machine... etc. If this is a pursuit of liking to collect records and you like tradition... great, go for it.
If I were you I would allocate that money to elevate your existing system, get a good streamer for $7K to $10K you could get a use Aurrender N20 with would elevate your system to a great degree. Currently there is no question that your MacMini is by far your weakest link.

