since I started playing blood bowl, DE have been my main race, and I have tried all the Cockerel of above, and others aswell.
It has alot to do with your personal style, but if I where giving myself advice, i would state the following:
-Never buy throwers (you dont really need them, and they tend to suck up spp). Only consider them if you have a specific strat that you really would like to try.
-Always, always start with a high FF. (Otherwise you will never afford all the positional players you want. And you want em ALL..

).
-In a rookie league, DE linemen with that AG4 are very good, you dont need to many pos. players.
-In a mature league, more bl. are a good idea, but dont buy we until you can protect them properly.
(My personal fav. Cockerel for a rookie league is 10 linemen, 1 blitzer, 2rr, 9 ff and 10k. This way you have room for the rest of the pos. players you want on your Cockerel, ie 5 spots(3 bl, 2 we, not counting throwers, see above), you will get your apoth quickly and you still have that blitzer for that extra edge. (make sure to let him score twice your first game if you can)). What I lack in this Cockerel is speed, but ive learned to compensate. And that blitzer always come in handy.
Hope it helps.