External monopropellant tanks, batteries and fuel tanks

External monopropellant tanks, which would make it possible to easily replicate this cool looking monopropellant tanks belt of the Vostok spacecraft:
https://en.wikipedia.org/wiki/File:Vostok_Spacecraft_Diagram.svg
https://en.wikipedia.org/wiki/File:Vostok_spacecraft.jpg
(if I recall correctly that those balls were monopropellant tanks, cause I'm not 100% sure)
It would also be cool to have external batteries and fuel tanks.