You seem to be asking which wheel is better, regardless of tire size.
Holding sidewall height and wheel/tire width constant, and using the same model wheels and tires, but allowing the overall diameter to vary, the best answer (which will be obvious to you the first time you attend an autocross event) is to run the smallest wheels you can that will fit over your brakes. Why? Because unsprung, rotating weight is one of those very critical areas of your car's performance. Of course, there is a gear ratio consideration involved with changing your tire's overall diameter, but we'll save that for another time.
On the street you want to keep your OD as close to stock as possible, which is why we talk about plus sizing. Now, if you run the same width tire (205, for example) in a lower profile, you will actually have a wider, shorter contact patch than you did before, which theoretically means quicker turn-in and better grip. (remember, 205 is the section width, not the tread width...) To get all the advantages, though, of that lower profile, you'll want to replace your apples with oranges. That is, find a larger wheel that is significantly lighter than stock--perhaps even wider--something like the Kosei K-1, for instance

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Grassroots Motorsports did a test a while back on a Civic with progressively larger wheels. Surprisingly, even with the greater weight of the larger wheels, their autox times grew progressively better. Still, you want to go as light as you can.
GRM Plus-sizing Test In most racing cases, wheel diameter is driven by brake diameter, and brake diameter is driven by heat management concerns. That is, the smallest rotors that are capable of managing the heat of track use are used. Beyond that point, larger rotors just add weight, as would the larger wheels.