Silicone saving
The plain formwork is a straight cylinder sized to your model's widest point, so anywhere it is narrower, silicone cures in empty space. Both options below remove that space.
Form-following makes the housing follow your model's shape. Works on any round vessel.
Silicone saver insert
v1 (beta). Assemble the housing on the base, pour silicone into the open top, then cast into the flexible mold you get. Best for straight-walled, cylinder-ish pots. Test print the yoke first to check the fit.