At the moment my Sims 4 game is Vanilla with the exception of the MC Command Centre. I installed the MC Command Centre because I am not happy with the speed at which the game runs at. Personally I think it is too fast and I just cannot do enough of the things I want to do within a day. So I slowed the game down with the MCCC only to find that the game increases the length of time it takes to do anything. This pretty much renders the ability to slow the game down as worthless.

Is there a mod anyone knows that can increase the speed in which Sims perform actions? I really need something to offset this. Personally I want to be able to double the length of the day and yet have it take the same amount of time (real time, not in-game time) for the sims to complete actions.

Anyone?

Relative time worked the same way in Sims 3. It's relative. Absolute time adjustment which doesn't slow down actions broke alarms in the game, which is why Deaderpool got rid of that option. Over time, you'll get used to it and won't notice it any more unless you're suffering from a bad case of simulation lag, but that happens even on vanilla. I play on speed 50 and it doesn't bother me, but I played with the Sims 3 equivalent (19) with the NRAAS Relativity mod, so I've just learned to accept it for what it is.

Twallan even said back then with Relativity that you'd notice oddities in your game related to time, if you slowed it down too much, all the way down to issues with how the clouds moved in the sky. It's the price you pay to have a longer day for your Sims.

There are many mods to speed up individual actions (like eating, drinking, showering, writing books, songs etc). I've been playing on 100 speed for over two years now and the only one I'm using at the moment is the eating one (I have all the showers upgraded and it helps a lot). Tbh, the only other thing that bugs me sometimes are yoga animations (lots of idle standing). I think relative time is somehow better (or just differently) implemented in ts4 — f.in. I remember in ts3 painting took ages with time slowed down — in ts4 I don't see much difference.

Indeed, both aparkison and insiderw have hit the nail on the head. To speed up actions in the face of slowed down time it really is a matter of adusting the preset timescales on any given interaction XML. But even then it's not perfect. The game can still introduce a bit of "whitenoise" interaction delay that occurs between the effects of slowed world time and sped-up interaction time. If the interaction produces the green dial icon in the sim's interaction queue, you can see how sometimes that shoots round quickly due to the interaction mod speeding the action up, but then a gap of whitenoise nothingness before the sim is released from the interaction to go do something else. It's a fine balance, to be sure. But I still prefer it overall than playing on default time speeds. Because that is too damn fast for my liking.

Come the day Maxis give us a time speed control in the Options Menu. That's the day I forgive them for all their past transgressions (Sim City 2013 included) and name my next child Maxis. (Like I'm going to have a next child at my age. More wishful thinking.) And if they ever made Sims 3 64bit, I would literally build a temple in their honour.... Damn wishful thinking. Gotta stop doing it.