It's not really the same thing. TBS (both parts of that; the TB and the S) are the core parts of the game. All features are built around that base, and the base is what defines the game. Large changes in features can make the game unidentifiable as Civ, but if you alter the base, you are certain to do just that.
@everyone that opposed a RT model, haven't you guys played, like the EU series of games or something? A StarCraft'ish realtime would no longer be civ, agreed, but an implementation similar to the way it works in Europa Universalis could be pulled off.
But, like I wrote, it's not that I'd consider ditching TB to be essential or anything, hell no, I was just trying to find a means to address several problems that have bothered me, personally, in the Civ series.
One of these issues I have is the flow of time. Unless you play one of the artificially longer modes, there's usually techs that "fly by", i.e. you never build even one of the units the tech unlocks. I feel in Civ5, it's even worse, because everything generally takes much longer to build.
Also, wars, and the time it takes units to travel places - it all feel's "off" to me in the earlier parts of the game. Having everything on a realtime mode would solve all that.
And when implemented cleverly, I don't see it destroying Civ any more than some of the features Civ5 brought to the table "destroyed" Civ -and they actually did, since I pretty much dislike Civ5 as it is now. Well, maybe I should say I'm indifferent to it - I bear no hard feelings on it, but I also feel no desire whatsoever to play it again.
Please note that, while I have played and enjoyed a multitude of RTS games, I'm also a big fan of TBS, and I loved games like the Civ series, MoM, MoO 1+2, Colonization etc. I just feel there's room for experimentation.
MoO2 (I pretend 3 never happened) came out 15 years ago, and in my eyes, there never was a game to dethrone it, but recently, there was a game called "Distant Worlds" which takes the TBS model to a RTS system, with many underlying systems that would be impossible or at least hard to pull off in a TBS game, and it works brilliantly. It's still not pushing the exact same buttons MoO2 is pushing, so to speak, but it takes the "4X in Space" genre into an interesting direction I COULD see the Civ series going as well.
That said (or written), I'd also be happy with a TB Civ6, as long as it contained other interesting changes implemented better than in Civ5, or - alternatively - moved back into the direction of Civ4 and the earlier games a bit like what Sulla outlined.
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rezaf