BEFORE ANYTHING READ THIS:
Honestly your enjoyment from the system will be very weighted by the games you like to play and how you like to play them. They have some really great titles and some that don't live up to the hype. I personally have always enjoyed things like LoZ/Mario/Smash so it is a fantastic system for me. More than that though the ease of travel with it as well as being able to watch Hulu/Youtube makes it an excellent system for me. Recommendations from my experience below with reasons.
Big Titles:
Legend of Zelda: Breath of the Wild
This one is fantastic for open world, non-linear-ish gameplay. The depth of what can be found and done is absolutely fantastic. Bear in mind that after around 50 hours or so, it can become repetitive but that isn't really a bad thing as you've already gotten 50 hours.
Smash
This game is wonderful (particularly if you have history with the series). It has multiple modes, and plenty of items to collect during your game time. Some levels can become frustrating, and the game can be "cheated" to unlock everyone quickly but it a great game for you alone or with friends.
Super Mario Odyssey
This game combines a lot of aspects of previous Mario games with that classic nostalgia. Very fun and vibrant with little things to discover along the way. I personally got bored of the moon grind pretty quickly but its worth a play for sure.
Pokemon Lets Go
Okay this one is rather controversial. I'll go ahead and make it clear now that this is not a clear cut remake of Pokemon Yellow. While it has a lot of that game it in, it also combines the gameplay of the mobile hit Pokemon Go. This has a lot of old fans rather unhappy but that is because the game is intended to be easier for newer generations/families to join in on the Switch console. Still a lot of fun, but be aware of the difference. (Also look in advance to see what game you want because some pokemon are not in the title you pick, rather they come from trading with others).
New Super Mario Brothers U Deluxe
Excellent game. Just know it is a combination of 2 previous games. Not much in the way of new content, but still crazy fun (particularly in multiplayer lol)
Titles You May Not Know:
RIME
This is very chill (my kinda style lol). Slow pace, Journey-like game that has limited action but is beautifully done. The mechanics are easy but never explained, as you learn everything by discovery. Look up the trailer for this, for real.
Dragon Quest Builder
If you like Minecraft but want more of a story/quest. This is a game for you. I literally put 2 months into level 1 haha. Very fun, and also very forgiving.
Overcooked (2)
Only buy this if you have friends to play with (in person or com). Holy shit this will drive you all nuts with the chaos that happens. I've never cried from laughing at game like did playing this with 4 players. God don't lose the fire extinguisher!
Rayman Legends
Nostalgia for damn days. Great side-scroll platformer. Kinda repetitive but its like all Rayman games packed into one, so there is tons to do.
Crash Trilogy
See Rayman Legends (but not just side-scroller)
Diablo
Ported pretty well. You do have to pay if you want to play online (as with all switch titles)
Tetris 99
Super fun if you like Tetris. Online only though so keep that in mind.
Don't Recommend:
Skyrim
You've probably already played and there are lots of reports (including mine) of the game struggling on the switch. Especially in docked-mode.
Fortnight
Literally sucks to play on switch. Seriously awful.
-Frost