Adding an item name to a relationship field in keystone.js

Does anyone have a good example of adding a name to a relationship field in keystonejs? Right now it just saves an id so if I need to display that fields name in a jade template I need to also query that relationship model. Ideally something like this:

var keystone = require('keystone'),
Types = keystone.Field.Types;

/**
 * Titles Model
 * =============
 */

var Title = new keystone.List('Title');

Title.add({
  name: { type: String, required: true, initial: true },
  room: { type: Types.Relationship, initial: true, required: true, ref: 'Screening', addNew: false },
  businessUnit: { type: Types.Relationship, initial: true, required: true, ref: 'BusinessUnit', addNew: false }
});

Title.defaultSort = '-createdAt';
Title.defaultColumns = 'name, room';
Title.register();

Would save like this:

title = {
    name: 'name',
    room: 3141234123442,
    businessUnit: {
        name: 'business name',
        _id: 123412341234
    }
}

If no example if someone could just walk me through the best practice on doing a custom relationship field type to store value and id from the relationship select menu I could probably figure it out. This site will have 1000's of documents in each collection so I need to focus on performance and best practices now.