The galactic center image won't be as fancy, unfortunately. Resolution of Webb is far-far-far too low to see anything related to the black hole, the best we could do is enhance the view of the stars near Sgr A* [1].
Webb resolution is about 0.1 arc-seconds (wavelength dependent) [1].
Event Horizon Telescope (EHT) resolution is about 25 micro arc-seconds (wavelength dependent) [2].
So roughly speaking, since you cannot really compare the two, since they observe on quite different wavelengths, EHT has ~4000 times better resolution than Webb. Note that we don't speak about sensitivity here. ALMA array of radio telescopes has a collecting area of 7000 m2, while it is just one of many "nodes" of the EHT. Webb total collecting area is about 25 m2.