To the extent that evolution is even adaptive (most of it is drift), greater fitness is just something heritable becoming more common in the population because it was conferred some advantage relative to the environment (with "environment" very widely defined).

The advantage itself could be all kinds of things, many of which have little to do with any common understanding of a "superior" trait. For example, female birds seem to (usually) have something wired pretty deep, genetically, that makes them hot to go for flashy feathers on a mate. Therefore, a gene variant that makes male feathers more appealing to a potential mate will tend to increase in frequency. Sometimes birds get kind of weighed down by their flashy feathers, so a gene variant that made their flashy feathers less costly (e.g., lighter) might often be advantaged. But over time this "give me a shiny mate" thing could, of course, change. In many animals, a seemingly common kind of "advantage conferring" gene variant is neotany, i.e. retaining some juvenile traits into adulthood. Like being able to drink milk into adulthood or when humans artificially select canines for puppy-like friendliness (like dogs) they tend to get the package deal and also acquire floppy ears (like dogs). Things like this aren't what come to mind when someone talks about "genetic superiority", though.

Re: Working towards a goal, this is exactly the opposite of how evolution works. It is a stochastic process where fitness is relative to an "environment " that is constantly in flux (though much more in flux at certain times than others). Vestigial traits are an obvious example for how there was no original plan or goal, just adaptation and drift over huge periods of time and in different environments.

This also applies to us, of course, but over almost unfathomable periods of time and relative to our environment that changes very rapidly due to our ability to consciously change it. Nobody can really tell you what is adaptive for humans at this point in time.