The cult of the new is pretty strong in modded Minecraft. To be honest, I haven't done much modded stuff in awhile, but 1.16.5 is a solid choice or at least was back when I last put a pack together.

Create is the big new mod that has everyone buzzing. In some ways it's a reaction to the RF-ification and magic blocks/multiblocks that dominated the 1.12 era. Everything is very nice and modular, and it reminds me of Rotarycraft in that respect, though they are very different mods.

Dang it, now I want to play some Rotarycraft. Reika has enough 1.7.10 mods that you can essentially put together your own pack of just them, but I digress.

I feel that most people play modpacks nowadays, but maybe I'm biased as a packdev. I've seen some good progression packs come out, if that's your thing. I'm biased towards my pack, Brass, of course, but Create: Above and Beyond is the official Create modpack with loads of custom content. I never got around to playing it, but it looks neat.

I'm running 1.19.2, my main mods are Create, Ars nouveau and minecolonies.

Create is likely my all time favourite. If you like industrial then you really should give it a try, especially if you appreciate steampunk.

1.16.5, it's peak modern Minecraft. I actually hate the new world generation post-Caves and Cliffs.

For me it’s 1.15. I really did not care for the nether update, but I think this is an unpopular opinion. Unfortunately doing modding on this specific version is not great. 1.12.2 obviously has the best modding support, but I really liked the 1.13 aquatic update.

There are surprisingly many mods already for 1.19 but there are also a lot which are still for older versions like 1.18, 1.16 or even 1.12. I'd recommend having a look at some packs with create. I think they are mostly for the newer versions. As for making a pack yourself, I do that a lot but there are also lots of good prebuilt ones.

I have always been playing on more modern version, but because of memes I started playing GTNH (greg greg greg) and I quite like it.

Good alternative to Gregtech on Fabric – Modern Industrialization. It's full of content, but without tedious parts that Greg has. And it's being updated regularly.

1.12 (Nomifactory GTCEu)