I am looking to upgrade from my current Afinibot Prusa i3 to a better one in terms of:

1) A printer that can print larger and taller objects

2) Faster printing time

3) Without compromising on the finishing of the part

Can anyone suggest a good one, budget below USD 1000?

Also, i would like to know if filament diameter play any role in determining the speed of the object being printed.

Example, if 20 mm x 20 mm x 20 mm cube takes 20 minutes to be printed (filament diameter 1.75mm), will increased or decreased filament size cuts short the printing time?

Thank you.