On a Mac with dual switchable graphics (iGPU and dGPU) the general setup is as follows:
Boot uses usually dGPU with limited, basic capabilities since the drivers aren't loaded yet. Once the GUI arrives the drivers for both iGPU and dGPU are available, full acceleration for both is available and the power management kicks in.
For graphics performance and power management Apple deems fit a rather simplistic scheme:
The default checkbox you see without gfxCardStatus means:
iGPU is used as default but anything requesting "real graphics power" leads to switching to the dGPU. Depending on the version of the operating system or the application this request could be quite arbitrary (e.g. just a simple Java stub with demanding graphics or a badly written app).
Influencing these settings leads to the following options:
So, in effect, yes, "Higher Performance" is the same as unchecking the checkbox in the first screen, that is, to force the dGPU.
Only using hacks – like gfxCardStatus – it is possible to get into the state of forcing more iGPU and better battery life (compared to – sometimes badly working – "Automatic Switching"). All the configs Apple seems to offer are more graphics power: force more dGPU and therefore force worse battery life.
It might be possible with a hack or maybe even to cleanly force the appearance and availability of the choice you seek in SystemPreferences.
But for your alluded usage scenario gfxCardStatus is the best and cleanest option available. If your system is still usable.
Cody Krieger's original gfxCardStatus is no longer under active development fot some time now. It is not the only option:
A newer/forked version (its development also ceased now) would be Steve Show's forked gfxCardStatus.
Please note: these versions of gfxCardStatus are a fine example for wisely choosing which version to use. The versions available have different options, abilities. The newest version might not be the best choice for what you want to achieve.
A seemingly similar desire as yours, avoiding gfxCardSatus, led to the development of gpu-switch
So that option might be the part of this answer that comes closest to your question.
Finally some precognizing: the point "because my discrete GPU has some issues" might need a more detailed approach.
If it is the AMD RadeonGate dGPU for MacBook Pro 8,2, 2011, I'd suggest lobotomising the dGPU with software out of the system. A complete guide for that would be here: GPU Problem. Further pointers to mitigating hacks for the most common issues for badly designed and manufactured MacBook Pros in the past are listed also in the announcement of ceased development here: https://github.com/steveschow/gfxCardStatus