I'm an evolution skeptic as well, because I don't buy the idea that it's solely based on random mutation and natural selection, which was what I was taught back then in school. It think that (in addition to random mutation) an organism changes bits of its genetic makeup depending on the environment it lives in/adapts to. And over generations (if the offsprings are living under the same environmental conditions), these changes to the genetic code get more and more refined. That's the only way I can see things happen the way they did.
Only a few days ago I stumbled over this article
that makes me think my hunch is correct. An organism that does sport like running recognizes what areas of the body need more support (like the heart, the lungs and the leg muscles). So everything is refined to change this. And the changes are also passed on to the offsprings. And if future generations run as well, these refinements get more and more prominent.
Adapt that principle to primates coming into a region with fruits hanging from tall trees, and over generations, back muscles got stronger and stronger, the shape of the spine changed, etc..., to refine the upright walk they needed. Furry animals relocate to a hot region, and over generations, they change their genetic makeup to produce less fur, or more sweat glands.
And organism absolutely knows what its doing and actively adapts to its environment. And the evolution theory I was taught completely ignored that.
accounts for at least some of the things you're talking about. Multiple "genes" may be present in an organism but only certain alleles are expressed due to environmental triggers.
Also, regarding human evolution, you're a little off as far as the chain of changes. Our ancestors were able to walk upright before they left the trees. Chimpanzees actually evolved back to knuckle-walking after our branches split. Neither had anything to do with reaching up to high-hanging fruit as far as I have read. We developed brachiation
Body hair is pretty uneven when you compare the temperature of environments and how hirsute the population is, and lots of animals have plenty of fur in very warm climates (it is good protection from the sun). A lion's mane certainly isn't doing it any favors in the hot African savanna, but other pressures apparently discourage any males born without one from breeding successfully enough for the population as a whole to be effected. It may be sexual selection, it might be the added protection from other males wanting to tear out its throat, whatever it is, it works. This is the randomness in action combined with behavioral pressures rather than environmental ones. Some lion running around half a million years ago didn't just think up the idea that it would like to have a mane and want it so hard that it was impressed into its genetic code.
In any case, perhaps you should read up on Lamarckian Evolution
which was one of the predecessors of Darwin's theory, and all the evidence that pushed us away from it.