Because I played all maps in Black Ops 1 and Black Ops 2 on PC my opinion can be different. I'm judging game mostly by gameplay, not story.
First of all, I started playing zombies when I got First Strike DLC for having MP Server. I turned on Ascension and I felt in love with this map. I found a group to play with and I spent a lot of time on Cosmodrone and Pentagon. Later we had CotD. I researched some information and I saw that there is an Easter Egg. I looked on map before and I realised that we had also ee on Ascension. I started doing them but I had to convince my friends for a long time (even now). Back to the topic, gameplay in BO1 maps was really nice. However, I didn't like most of the weapons from box, I enjoyed using Ray and Mustang&Sally (or ThunderGun if I had it). Later they added this zombie bosses. In Shangri-La I liked them. But in Moon and CotD, George and Astronaut re pain in ass. I hated them. Characters, well O4 is just epic. And these Easter Eggs... I hated one thing, they were too long. It was really hard to convince my buddies to do it (especially Shangri-La, 4 players, 4 times to repeat urgh).
But DLCs ended, 2 years of waiting and we have new BO2.
Let's start with possitive changes.
First, NEW ENGINE. This is just epic. Why? Because in BO1 I had 30 fps, 10 fps if i look into water on medium graphic, resolution 1024x768. BO2 ? 60 fps, high graphic with anty-aliasing 4x, resolution 1920x1080. The same computer. This is the HUGE plus for Bo2.
Second, BOSS Zombies. Avogadro, Brutus. I feel like it's easier to kill them. Avogadro, 2 shots from Galavaknuckles, NO PROBLEM. Brutus, Ray Gun and I didn;t have to use so much ammo how I had to on Astronaut (yeah, brutus is running but it's not a big problem for me). Also, I like return of Boss Round- Minions in Die Rise.
Third, Leaderboards re now better. Less cheaters (in BO1 there was a lot of them) and it's more expanded.
Fourth, the game doesn't depend only on wonder weapon and Ray Gun. Actually, normal weapons (Galil, An-94, Pdw, Aks-74u, Tommy Gun, RPD, LSAT, M27 re my favourite) are more useful. Sorry but I didn't like using any weapons in BO1 if it wasn't Galil, Aks-74u or WonderWeapon / Ray Gun.
1. I don't like Tranzit. Few reasons- fog, long time to craft Jet Gun and lava. And this was the first map so BO2 didn't look good for me at first.
2. Custom games with normal settings COULD count to leaderboards :/
3. Some people say that in Black Ops 1 u don't have to be online to play Solo. Well, when I want to play solo game in BO1 and servers don't work - I can't launch solo. It wants to connect to servers anyway. So there is no problem for me that I have to be online to play solo. The problem is when Steam Community turns off for even 10 sec, YOU RE KICKED FROM GAME. 54 Round ? Too bad, dc.
4. We lost that climate from WaW. Maps in BO1 weren't as scary as in this WaW and maps in Bo2. It's not even close. Only MotD, I must admit had this climate.
5. Gersch Device, R.I.P.
6. Radios, R.I.P. New TV system sucks.
7. Elena Siegman's songs R.I.P. (But I love Malukah. Sad that she appeared so late)
In the end, there re some possitives and some negatives. But from my view of PC Player, New Engine gives nice advantage for sequel. My verdict is 8/10.
P.S. GIVE ME IN LAST DLC ALL MAPS FROM BO1 BECAUSE I HATE THESE 30 FPS AND I WON'T PAY 4 DLCS AND GAME ON PS3 AGAIN