ive been playing this game since 2011 when i was in middle school and im still coming back to it. im sinking hours into it after work while my puppy sleeps next to my desk and my gf is working evening shift. its such a cozy game and reminds me of when i spent all day after school playing MC and other games w friends. its not just nostalgia tho, its just such a cute game that can be whatever the player wants. after all this time, i still derive so much joy from exploring a new world, building a sprawling estate, spelunking, and even just mining. even tho MC doesnt track ur hours played, im certain its my most played game
just wanted to share that i love this game 
Create is mandatory for me, and many of the addon mods like the one for hooking up Create to RF networks are nice.
If you like coding, ComputerCraft is awesome.
There are lots of tech mods that come and go, like EnderIO I think recently got updated which is nice. Mekanism is very ubiquitous as a tech mod with all the necessary parts to play through.
Hex is a really interesting “programming” mod. It lets you make wands and create spells by combining different symbols together, with a kind of programming logic to it that allows you to get arbitrarily complex. I haven’t had much chance to play with it but I’ve seen people make spells that dig out quarries, build geometric shapes, duplicate builds, etc.
To me, the thing that’s really fun is just having reasons to build an expansive base. In vanilla, all you really need in your base is an enchanting room, crafting tables, furnaces, and maybe a couple farms. In modded you make a: