If you're looking for a waac army, take into consideration your play style as well. The army can be as cheesy as it gets but if you don't know how or don't feel comfortable playing it, then you're not going to be getting good results against smart players. If you've got a hyper offensive style, where running across the table full speed is what you like to do (since OK have already been taken), don't go for a very defensive army, go for DE, DoC or WoC. If you're more of a defensive player, then go for a lizardmen MSU army. If you're adaptable, then go skaven, who can go offensive or defensive and still be effective!