A lot of surgeons are posting their results online. You could have a look at Dr. Miro or Dr. Crane's websites. They both have a pretty good gallery of different results. I would say the outcomes now are very good in terms of aesthetics, sensation, and function; especially when you compare them to how things were a decade or more ago.
There are still areas for improvement, such as erectile implants for phalloplasty which have a high complication rate currently. But as far as the basics go, things have improved a lot.
If I had to estimate or hypothesize how much more advancement there could be, I would say that metoidioplasty is probably about as advanced as it will get. Phalloplasty as it exists now in its most popular forms (RFF, ALT, MLD) will probably not change as a procedure. I do foresee continued improvements in erectile implants, as companies continue to offer new models with improvements regularly.
