So, you're disabling things that either you don't really know what they do or things that don't affect any way you use the computer?
Why not just leave this stuff how it is?
Because they're "... things that don't affect any way you use the computer" but they're not free in terms of resources (though many may be very very close to free). You could just buy a faster computer, but often it makes more sense to optimize the software side until it runs fast instead.
I represent a fairly extreme case of this. I didn't care about gaming for a while, and absent that, I did nothing with a computer that intrinsically took a lot of compute power. In that time, I used a variety of computers that the average user would consider hopelessly underpowered, most notably a single-core Atom netbook and (as recently as a year ago) a northwood Pentium 4. I never had problems with the performance of any of these, thanks to:
* an SSD
* lightweight desktop environments (LXDE or Xfce, more recently straight Openbox)
* attention to detail (the relevant one)
Attention to detail means stuff a lot like the subject of this thread - making sure the computer isn't doing stuff in the background that it doesn't actually need to be doing (if you can help it). Like I was saying, I'm an extreme case, but this sort of work can occasionally be the difference between a system that's snappy enough it doesn't really matter, and one that's merely usable.
So is it worth the OP's time from a strict effort/performance perspective? Unlikely. Is it worthwhile to know how to do? I think so.
(Also, it may not be strictly a performance thing. Even absent resource use, CEIP sounds like something I'd rather not have running.)