I still think you're oversimplifying the experience a lot (particularly on boss mechanics). You'd be surprised how much boss mechanics can carry the experience--in fact, that is probably the driving force behind the fun. Regular mobs are dull as hell, but hey, the bosses aren't half bad. i.e. things like dynamic LoS, splitting up the group, heavy positioning requirements etc. That is where the appeal is. Your misgivings seem a bit dated. WoD is definitely a different experience than pre-Cata.
I know that encounter design has changed a lot over the years. And it's also not like I never had fun playing WoW. I certainly wouldn't have been part of progress raiding back then if I hadn't had any fun.
The insight on how limited this game is in terms of replayability came when I leveled up my third twink. At this time, I had a priest, a warlock and a warrior. I tried to find variety in combat, but couldn't. In the end, I always have my spam, my low CD nukes, my opener and my situationals. On every class. The priest offered the most variety in the way that I could also heal with it. Which is why I changed to a holy priest at level cap and started progress raiding. I participated with both warlock and priest on raid content.
Playing warlock in a raid was boring as hell. Summoning people had a social component to it; for some weird reason, I enjoyed that mechanic the most. It felt like I actually made a difference. Like I wasn't just a walking random number generator. Also, the warlock had some fun spells to dick around back then, like summoning an infernal that turned hostile and had to be enslaved, or a fel guard. I wished WoW had more of these abilities.
Playing the priest in raids was more fun than the warlock, due to me actually having to react to whatever happens dynamically, instead of just spamming a fixed rotation. But then I realized one thing which destroyed all the fun I had in tab-targeting combat forever:
I wasn't even looking at the actual game anymore. I had my eyes fixated on the raid window healthbars and nothing else. Or on the boss frame to check out what spells it casts. Or the raid warnings or buffs.
And I wondered: how is this still a "game" experience if the UI is more important than what you actually see on screen?
And then when playing Tera, I had this one moment that sealed the fate of tab-targeting combat for me:
I was in a dungeon with a friend of mine, two randoms and one guy that seemed to be an experienced highlevel player on a twink. Nothing special in particular, I thought, and then we went into the dungeon and wiped at the final boss. The boss was still on 50% life; everyone was down except the twink guy. I was preparing to res myself and walk back in, when this guy said in teamspeak "no worries, I got this!". I thought he was kidding, but then he just kept dodging every single attack, taking only a couple of hits while slowly wearing the boss down. It was a moment of ultimate badass. And I was like "How the fuck is that even possible?". I felt like a complete noob not being able to pull that off. For the first time in my MMO experience, I felt like I had A LOT to learn before I could compete with the progress gamers.
Now, to come back to WoW - please don't get me wrong here: TERA is a shitty game outside of the combat. The combat is absolutely genius (the controls could feel a bit more responsive, though) and the F2P model is decent. But that's it. The game has nothing else to offer (except maybe for the asian graphics and some fucking weird costumes like a panda riding a ... bigger panda?!). In terms of gameplay, quest and zone design, this game is no comparison to WoW. And that's why I quit playing the game. The combat is extremely fun, but that alone won't make a game, unfortunately.
When thinking of WoW in this regard, it's just that this game could offer
so much more if the devs would just embrace the evolution of the genre. Contrary to popular belief (aka the belief of WoW players), the genre HAS had some significant innovation over the last decade.
