Modifiers matching neutral:

• small,
• abundant,
• dark,
• earthy,
• pale,
• soft,
• energetic,
• urban,
• warm,
• natural,
• impartial,
• new,

Simple categories matching impartial:

• entity,
• party,
• institution,
• body,
• consultant,
• organisation,
• neutral,
• professional,
• group,
• person,
• agency,
• authorities,
• observer,
• commentator,