Any specific performance goals, or just appearance? I don't think you'll notice much difference in appearance if you choose the right tire, but over the years there have been shifts toward larger wheel sizes. When I was a kid, 15" wheels were the special thing. 13-14 was the norm. Imagine my surprise when my 1996 Impala SS came with 17" wheels from the factory...whaaa???" Now pickup trucks come with 22s and 24s, and Corollas come with 18s.
It's even getting tough to find appropriate 15" tires for a Camry, let alone a large, full-size classic. A lot of the 15" options left are 185/65 stuff for things like a Nissan Leaf or a Toyota Yaris. 16" will open up many more options.
Going from 15" to 16" will have a (completely un-noticeable) negative affect on acceleration. If you were going from 15 to 18, I would say you might notice a difference, but 15 to 16 you'll never notice. The shorter sidewalls, however, might make a tiny difference in handling (again, depending on the tire you choose), but unless you've done some serious upgrades to the Sedan's suspension, it's a moot point.
I mentioned all of that to say: If you do upsize, do it because of appearance and/or tire availability, but it won't really affect any performance aspects.
