There are a few places I’ve found with lots of prebuilt monsters for GURPS, though they aren’t really consolidated in one place. I usually look through one if the following if I want something prebuilt:

• the creatures of the night books (mostly solitary monsters you could design an adventure around, with suggestions for each one)
• the fantasy bestiary (lots of generic and mythological monsters from all over the world, with stats and descriptions for each one)
• dungeon fantasy monsters 1-3 (lots of monsters, kinda built with dungeon fantasy settings and power levels in mind)
• the gurps repository also has tons of free and generic statblocks

I’d recommend Kingdoms of Amalur if you’ve never played it. It has neat lore, and the combat is fairly satisfying imo. My main complaint is that combat gets kinda easy when you start approaching the level cap, even on max difficulty, but I still go back to the game every now and then.

Why? I generally find it pretty easy to avoid unhappiness, and if I’m building bases in different biomes for the pylon network, it’s just a bunch of free discounts.

It’s real: https://www.youtube.com/watch?v=cC1CqyCN9Q0

I’d say it holds up extremely well, especially with mods, but your enjoyment will depend on what you look for in a game.

The sandbox and exploration elements are the best part of the game IMO, but if you don’t care about that kind of thing, you might not like it.