You'll find that you don't want a polarizing filter as a protective filter. Why? Because it cuts out 2 stops of the precious light that we all want as much of as we can get to work with. They are great for their purpose of cutting reflections and making the sky darker. But indoors or whereever it's dark, you do not want a polarizer on our lens in almost all cases.
That's what makes UV and Skylight filters best for their protective qualities. They don't do a lot to change the photos, but they do help very much if your lens gets dropped, bumped, dragged across something sharp, etc. It is way easier and cheaper to replace the filter than the lens. UV filters do cut some haze out of distant skies, and Skylight filters usually have a slight pinkish warming tone to them. Neither one cuts out enough light transmission to worry about.
Yes, this is an expensive hobby we all are working in. After you save the money to get some higher quality equipment you'll understand why it costs more. Tripods are one area that I really think that it's worth it to buy a good sturdy Manfrotto or Gitzo or the like.
I went through several Slik and bargain brand tripods before getting my first really good one. They seemed to do the job, but joints and parts wear quickly and the legs become floppy with use. If your camera and lenses are fairly heavy, there's always the danger of tipping the tripod over. Then you go back to hoping you have that protective filter on the lens!
Can you tip over my Manfrotto legs? Yes, but only if you try really hard or aren't paying attention to where you set them up. I feel very comfortable with my gear on them, and that wouldn't be the case with a Slik.
In understand the expense of things, but many times it is just plain worth it to save up your money and get the right stuff.