Soaking chunks, wash your mouth out young man!
Like you mentioned earlier, it all depends on how much smoke you prefer,and it also which wood you are using. As an example, personally I do not like to much Hickory so I only use a couple of chunks. However I love Oak so I throw a lot more on the coals. If I am mixing Apple & Oak I will use more Apple than oak as the oak has a stronger flavour, and I do not want to overpower the apple.
To cut to the chase it's all a matter of personal taste and personal preference. As Wade mentioned earlier, there is no right way only the wrong way when it goes in the bin. (as my wife occasionally reminds me about the leg of lamb).
It's a trial and error thing, take notes of temperatures, how many chunks you added etc. and them critique your food at the end. That way you will have a reference for the next time, and you can make adjustments accordingly.