Hi Eddy.
Like you, I am not into tour packages. I prefer spontaneous activities and doing things at my own pace, and I would generally explore on my own or have a personal guide. I have never been to Tibet, but I am going back to Beijing either this summer or this fall, but I do not know when.
Tour packages have pros and cons. One of the cons is that they tend to bring you to places where they try to get you to buy things... often expensive things, and you end up wasting much of your time wondering around stores. If you do decide to join a tour, I would suggest signing up through your travel agent or at the reputable hotels once you are there. There are lots of fake tour packages in Beijing! I almost got scammed during my last trip, but my local friend was smart enough to research on the fake agency.
If you do not speak Mandarin, then I would suggest either having a personal guide or joining an English-speaking tour... othewise, you risk the chance of getting lost, getting cheated, or doing things that's forbidden.
Anyway, enjoy your trip. I had a great time in Beijing.
