Can I do something like Resource.Load, but pass it a GUID instead of a path?

It would be nice to load by GUID, so we could rename stuff without worrying about our Resource.Load calls.

Uhm, no. The actual asset GUIDs are only used inside the editor to track an asset inside the project. That GUID is actually in the metadata file and not part of the actual asset.

The point of “Resource.Load” is that you can load resources by name. If you want to directly link stuff (which would be better anyways) you should assign that asset to a serialized variable in the inspector. That way you can rename your asset with inside the editor without any problems.

If you don’t have a reasonable class / asset where you could link those assets you can create a dedicated “asset manager” ScriptableObject.

For example something like this:

//AssetManager.cs
using UnityEngine;
using System.Collections.Generic;

[System.Serializable]
public class AssetItem
{
    public string name;
    public string guid;
    public Object asset;
}

[CreateAssetMenu( fileName = "Resources/AssetManager", menuName = "Create AssetManager")]
public AssetManager : ScriptableObject
{
    private static AssetManager m_Instance = null;
    public static AssetManager Instance
    {
        get
        {
            if (m_Instance == null)
                m_Instance = Resources.Load("AssetManager");
            return m_Instance;
        }
    }
    public List<AssetItem> assets;
    public static T FindByName<T>(string aName) where T : Object
    {
        foreach(var item in Instance.assets)
        {
            T tmp = item.asset as T;
            if(item.name == aName)
                return tmp;
        }
        return null;
    }
    public static T FindByGuid<T>(string aGuid) where T : Object
    {
        foreach(var item in Instance.assets)
        {
            T tmp = item.asset as T;
            if(item.guid == aGuid && tmp != null)
                return tmp;
        }
        return null;
    }
}

This class allows you to create a ScriptableObject which you should save into your Resources folder and give it the name “AssetManager”. Now you can simply edit it in the inspector. Just add as many assets you like by increasing the list count, and dragging your assets into the “asset” slot of each element. You can give them a freely choosen name and guid (which both are just strings).

It provides two static methods which allows you to find and return an asset from that list based on the custom name or guid you have given it. Since those are generic methods you can directly let it cast the result to the wanted type, just like Resources.Load does.