Yeah it's got some great additions in my opinion. It's not as necessary as it used to be thanks to valve slowly adding in many decky plugins into standard SteamOS.

Some nice plugins for usability:

• autoflatpaks: update flatpaks from game mode
• battery tracker: track average power usage of games over time. Good for getting an actual average power use for games with a wide range of battery drains
• Junk store: install epic (and GOG if you spend $6) games from game mode
• KDE connect: get notifications from your phone, use your phone keyboard to type on the deck
• MagicBlack: turn off screen on the OLED version for saving power during downloads/etc
• Pausegames: lets you pause any game, freeing up resources without closing it. Lets you pause games that can't be paused, run multiple games at once, and can fix audio issues when suspending
• Playtime: tracks playtime per game and per day
• protonDB lets you see what games will run on the deck, even if they're not steam verified/etc
• powertools: lets you adjust cpu cores/clock speed etc. Lets you get super low power usage in some games (down to 3.5w or so), and fixes some games with bugged cpu speeds
• shotty: moves steam screenshots in pictures folder to make them easy to find in desktop mode
• steamback: makes backup saves of your games everytime you open or close a game.
• volume mixer: change volume balance between programs. Very helpful if you're using discord/etc while playing.

There's also a ton of nice customization ones, which I can share if you're interested.