As it is only a matter of luck that ur site gets added in dmoz, what is more viable for longer term - to get a paid yahoo listing & go on building backlinks for the site or to invest in PPC campaigns. I think that PPC is good for analysis purpose as to which keywords can drive maximum traffic but in certain cases PPC is too high and is almost unviable to continue, moreover i donnt think anybody can beat natural listings. What should one do more to get top rankings in google rather than optimization, yahoo listing, one way links, pr releases, article submission......
An important one you missed is keyword research and using the best anchor text possible. You just need to find a few keywords to optimize for that many dont and it is much easier to climb the ranks on Google. Placing you link on directories doesnt do much good unless you are using the appropriate anchor text.