We've recently added some features to the Workshop that should be pretty useful for both new and power users alike.
The new Steam Client beta has various improvements around Workshop, including displaying which item is being downloaded in the Downloads page, and an improved interface for dealing with your Workshop item subscriptions (accessible from your game's Properties dialog). The subscription list now contains additional information, such as when the item was last updated, when you subscribed to it, and any item dependencies. You can also filter your list by name or by tag.

For more advanced use cases, you can disable items from being loaded by your game. And you can now change the local load order for your items. Also, if Workshop creators have set their items as depending on other items, you can automatically set the load order based on these dependencies. Missing dependencies will also be displayed, to make it easier to see why some mods are not working. You can opt into the Steam Client beta to try out these changes.

On the web side of things, we've added Saved Search Queries. Basically, if you often find yourself searching/sorting/filtering to find the same kind of items in a game's Workshop, you can now save those search query parameters. Then you can re-run your search at any time by selecting that saved search query from your game's Workshop home page.
We've also added some more browsing options to the main Workshop Home page. You can now filter to games that have Workshops based on whether you recently visited them, and we've brought back the ability to view Workshops for games you own or have recent playtime in.
Plus a few other web changes:
Let us know your thoughts in the Steam Client Beta discussions.