Stock tire size or slightly larger diameter?

I have a 2015 c Three with stock alloy wheels that I just measured to be 6" wide (but may really be 5.5" if that is meant to indicate inside the beads, which you can't measure with tires on). She currently has the stock tire size on it, and I'm in desperate need of new tires (I assume they are original with 51K). I don't necessarily have an issue with the OEM size, but it limits the options and if anything I'd like more ground clearance. I'm also OK with slight hit to MPG.

Looking at Tire Rack, for example, there are only 23 options in stock size vs 41 for 195/60R15, which is 0.2" larger in diameter, or I'd even consider 185/65R15, which is 0.5" larger in diameter and has 42 options.

It's too bad there isn't a way to tweak some thing in Techstream to keep the odometer accurate, but I'm OK with that too.

If needing to use the spare, which is significantly smaller than stock, I'll move it to the back if a front tire goes.

Is there anything I'm not considering if I find a good deal on one of these two larger diameters?