Modifiers matching neutral:

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

Simple categories matching impartial:

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