The Nintendo Switch was the best gadget of 2017. That's my opinion, but I dare you to disagree with me. What started as another odd Nintendo novelty gaming design has turned into a runaway smash success. The system has sold over 14.8 million units worldwide, more than the Wii U ever sold. Some of the best of games of 2017 -- notably Super Mario Odyssey and The Legend of Zelda: Breath of the Wild -- were Switch exclusives, and the console's game library has continued to add a long list of third-party favorites, reversing a big weakness of recent Nintendo consoles.

So, a year after excited fans lined up to buy the Switch on day one, what's next? Actually, there's a lot that can still happen for a second act with the same hardware.

Add more modular accessories

The most brilliant idea of the Switch is that it's a modular tablet: between its side-rail connectors for Joy-Con controllers and its USB-C port on the bottom, all sorts of expansions are theoretically possible. A Wall Street Journal report seems to confirm Nintendo's peripheral-based strategy, which makes a lot of sense -- why upgrade the tablet part right now? The USB-C port works for the included dock and video out, but it could allow other connections and accessories, too: USB-C is very versatile.

The rails that the Joy-Cons slide into are used for controllers now, but they could clearly accommodate other ideas. Nintendo hasn't opened up third-party access to those connectors, but Nintendo has hinted before to new ways to play in the future going back to last year, when Nintendo spoke to CNET before the Switch launch. I'd like to see a more advanced and better-fitting dock, different sizes of controls, and maybe a version with full-analog triggers.

More crazy things like Nintendo Labo

Nintendo Labo is one of those "new play" ideas, and it completely sidesteps any plug-in hardware. I tried playing with the kit, which is brilliant -- it's like programmable papercraft with a tied-in video game, and it utilizes the sensor and button-studded wireless Joy-Con controllers to power all sorts of other ideas.

Nintendo's done a clever thing with Labo: it's shown that the included hardware is already more versatile than it seems on the surface. Labo hits stores in April, and I'm hoping Nintendo will follow up in the second half of the year with something equally and wonderfully bizarre and creative.

Improving the online experience

Will Nintendo's subscription service upgrade the online experience that's on the Switch now? A number of Switch games are online-friendly, and Nintendo even has a (not great) phone app to connect to online game chat in titles like Splatoon 2. But the fuller subscription service is slated for later this year. It'll no longer be free to play online. Hopefully, however, the online experience will be better in exchange for the yearly charge. There's a lot of room for improvement.

More old-school retro games

Nintendo's affordable retro-game plug-and-play console, the NES Classic and SNES Classic, are still pretty hard to find. But you can't play any of those NES or SNES retro games on a Switch. Not yet, at least. Nintendo's kept its back catalog of virtual console and retro games mostly off the Switch so far, but the launch of the company's subscription online service in September promises access to the titles that Nintendo 3DS, Wii and Wii U owners take for granted. Needless to say,  it'll be frustrating paying for the original Super Mario Bros. for the fifth time, but fans will love playing classic games on the go on this modular system.

There's also all the Wii U games, ripe for rerelease: the Wii U was a system few even got a chance to play. It worked for Mario Kart 8 and Bayonetta 2. There's a lot more where that came from: Super Mario Maker, Super Smash Bros., Super Mario 3D World, New Super Mario Bros. U and Nintendoland.

A flood of indie 

The Switch has become one of the best pipelines to try indie games over the past year. I'd even say that the indie games have become my favorite things on the system. Ports of popular Steam, PlayStation 4, Xbox One and mobile games like Rocket League, Thumper, Stardew Valley, Overcooked and Celeste are now starting to arrive as simultaneous Switch launches. The games can often cost more on Switch, but take up less space to download and are perfect for quick play. Now that the Switch has sold so many systems, it's no longer a risk for indie developers to plan for Switch releases at all.