By Itself that change makes Athens a hugely more convenient city for those visitors on a budget and for many residents.
Even the Green Line or the elderly Electriko has been given a whole new look and backbone and as for speed, well, all the lines are just about as fast as you could ask for. .. that means fast where they have enough room to build "a head of steam".
People with special needs enter the major terminals from free standing glass elevators outside (pic is the people with special needs entrance at Panepistimiou Station.)
The National Archeology Museum and Acropolis have special access entrances too!
The Metro's Cars and hallways are clean too - so far! The persons responsible for that policy should get a medal - there is no graffiti yet either. However, the glass is scratched on many car doors and windows to the detriment of us all, so those little blighters are out there but somehow kept in check. They have magic markers but hopefully will outgrow them soon! Graffiti is Greek word unfortunately.
The Athens Metro is also faster than driving and you can depend on its timetable more as its not subject to the vagaries of Athens notorious traffic jams. The metro has delays too but not often.