In Warlords I got major slowdown in late game in a standard game (I can't play higher then Standard becuase my System can't take it)
But In Original Civ 4 I was pretty stable after 1.61 patch
So will BTS bring back whatever stability was lost in Warlords?
Or will it overall create a more stable game?

In short, don't count on it.

Because they've exposed many more of the SDK to Python checks, it is likely the late game especially will suffer from slowdowns. I say this because Python checks are one (but by no means the only one) contributor to lag. Kael's Speed Mod works by getting rid of these, for instance, but the downside is that you can't use it for mods because by its very nature it gets rid of all those things that make modding easier!

My hope is that they realized this and figured out how to get around it... but don't hold your breath... :sad:

Yay Hope is good becuase if you are a low end user please continue to hope that it will be fixed up :)

what are you considering a low end user? I am still using a single core cpu >.> 3.33ghz but technically that is low end in todays age of dual cores. (rest of specs that matter are 2gigs ram and a Nvidia 8800gts 320mb.(I went a bit cheapo on that card just didnt want to spend 400 or more for the slightly better versions))

In short, don't count on it.

Because they've exposed many more of the SDK to Python checks, it is likely the late game especially will suffer from slowdowns. I say this because Python checks are one (but by no means the only one) contributor to lag. Kael's Speed Mod works by getting rid of these, for instance, but the downside is that you can't use it for mods because by its very nature it gets rid of all those things that make modding easier!

My hope is that they realized this and figured out how to get around it... but don't hold your breath... :sad:
Exactly that was one question I asked in the chat. My question was if the included a feature like the speedmod where all unnecessary python checks are disabled (because most of the civ players play without a mod).

But if it is not in the expansion, I hope we will get a speedmod for BtS right after the release.
Also the feature with the EDU will not speed up the game :).

Don’t understand me wrong. I’m a big fan of these new features! I only hope there is an option to disable things that will slow down the performance in the late games on big maps with many civs.

Interesting... how would one disable these "extra" python checks? I use no mods at all, and 99% of the time play single-player, custom games. A little extra performance and speed is always nice.

The best way to disable the checks is to download Kael's Speed Mod. :)

It's been years since Civ4, maybe it's time to consider an upgrade?>

if by years you mean 18months......