Yep, contracting is not for everyone
The main risk with contracting is what you call "bench time". The longest such period I had was 8 months in 2002 ( I have hard of as long a 5 years benh time) and, while I survived my finances have not yet recovered. The other risk is you may have a choice between no contract and a contract that means slow financial death. A third risk is that your contract path is, whatever you say, a random walk, and may walk you into a vanishing niche. There are other risks but I won't discuss them here.
If you need a predictable income, cannot take the stress of uncertainty and your financial management skills are weak, do not go contracting.
FOr myself I am working slowly on ways of generating passive secondary income streams so "bench time" is less of a threat. This is harder than software development.
