why do you want power saver if you disable all this things?
Because power save is not a simple "set those values low".
I've tested the battery life with my nokia c7:
1) With power save enabled
2) With power save disabled, but same settings as power save mode
The battery life is much shorter in the second test, compared to the first one (~2.5 days Vs ~4 days).
So, power save do something else other than set those values low.
And so, changing back those values won't remove all benefits from power save mode.
Anyway, those values can be set to something lower than the normal mode, but not so low as the default power save mode, because IMHO they are too low.
Also I get bored every time it says "You can't change this in power save mode", especially with settings like the theme effects, which are not touched by the power save mode, but it won't let you toggle them for some unknown reason, and I have to disable the power save, toggle the theme effects, and re-enable the power save.