T57 is still strong and has potential to be OP, just dial back on the nerfs WG gave it to gun handling and reverse speed. Its gameplay role (high-DPM large-clip autoloader) always had potential to greatly influence battles beyond the tank's raw stats and thus the tank had to be hobbled by the nerfbat to keep it in line.
Good gameplay or new equipment (as Alex alluded to) can undo those nerfs. The new Mobility Improvement equipment buffs both gun handling and reverse speed, kinda like Turbo+IRM, and can stack with VStabs. Then go for Vents+BiA+Cola now, and wait for Crew 2.0 this year for even more gun handling buffs.
So it depends on how fast you grind. You grind fast, you can follow the meta and get the Vz55 and enjoy its current position in the meta.
Otherwise, if you grind tanks slow, by the time you get the T57 the meta may have shifted back in its favor.
I'm fierce and I'm feeling mighty,
I'm a golden girl, I'm an Aphrodite
