Gothic 2 is arguably my favourite RPG, and has been for many years. It features exiting fights, lots of different skills, three different 'paths' to choose from, and loads of things to discover.
First, the positive:
Gothic 2 is much smoother than Gothic 1. It's easier to use, less clunky, and merchants are easier to deal with now that gold is introduced as opposed to trading items all the time. Timing is important during fights, but so is picking your opponent.
Gothic 2 doesn't hold your hand at any stage of the game: if you make the mistake of wandering into the woodland armed with a wooden stick at level one, well, it's your funeral. The NPC's give advice, though, but you'll have to find them and ask them.
You'll also have to build your character from the ground up: you start with a little health, and a huge problem the game needs you to solve.
Levelling always feels important and vital to the game, be it your stats or your gear. The game makes every improvement you make feel valuable. This is because if you don't level up and face something stronger than you, chances are you're going to die.
All this makes playing the game incredibly rewarding. I felt genuinely satisfied every time I accomplished something, because I worked for it. Gothic won't punish you by being overly difficult: it'll just make you work.
But just in case you get too stressed grinding through the game, don't worry. After you get strong enough, you'll find some enemies easy to throw around if you skip around some of the earlier stages of the game you missed before. Destroying things that once scared the pants off you makes everything feel better. This feeling will dissapear if you accidentally stray next to a higher level enemy quite quickly though, keeping an incredibly fun cycle of victim and bully going strong until the end of the game: it never gets dull. Either you're happy and feel like a boss, or you're running for your life, and it's not something a game does for me often.
Exploration is also rewarding: loads of secrets are hidden all around the world. Some of the best items and deadliest enemies lurk where you wouldn't expect. Sometimes quest items or NPC's can be hidden in the middle of the countryside, but unlike Skyrim, you can't follow a little arrow on your compass until you come across it. Find it on your own.
As for the world itself, it's an open world, but that doesn't mean you can go anywhere you want. Higher level monsters lurk in some areas and mountains and cliffs box you in a lot of the time. This means that over a small area, there can be a lot of stuff that's hidden: under an ordinary country road could be a huge cave full of glorious, glorious loot, but at the same time, on top of the cliff to your left might be an epic monster, and you'd never even know unless you looked.
Now, the bad:
I had problems getting Gothic 2 to work on my computer. Whilst I eventually got it to work, it's a messy problem that took a patch to fix. There may be betters ways to get the game than on Steam.
Night of the Raven messed with the levelling system a lot. Before, I found the game to be difficult, but fair. Not so much now: items need much higher strength to use. This means you have to gain more levels just to use a sword you could previously use at a lower level. You also end up needing to go up even more levels to gain more stats, which was frustrating considering that I was having a hard enough time facing orcs before Night of the Raven. I didn't really appreciate the content it brought to the game either: in a world of dragons, knights, and medieval monsters, I didn't really think that pirates or aztec temples really fit. There was great nostalgia value from meeting some of the characters from Gothic 1 in the expansion, though, but I didn't feel they balanced the stuff I didn't like enough. If Gothic came without Night of the Raven, I would have much preferred that... either that or I became a bad player over these past few years (which I doubt).
Finally, the gameplay might not please some people. I spent a long time praising Gothic 2 for being difficult and rewarding, but for a more casual player, it may be a bit too brutal to get used to. The fighting system isn't the same as anything I've ever seen, and it isn't the most fluid to use. Sure, with practice, you get it, but you may not necessarily want to.
And now, my closing statement:
Gothic 2 is a classical fantasy RPG that combines some of my favourite tropes from the genre: wizards, knights, and epic, evil, hard to kill, not-at-all-watered down DRAGONS, but without making it feel too generic. The wizards (oh, I'm sorry... fire magicians) feel halfway between priests, scientists, and diplomats, and the dynamic between the paladins and the mercenaries is really well done. Choices you make have some of the most unexpected consequences making choosing a path truly unique and giving the game some great replayability.
Gothic 2 with Night of the Raven: 8/10
Gothic 2 in all it's glorious alone-ness: 10/10