Seems like most of your bulls come from two or three breeders. If I didn't trust their information, I certainly would not carry their bulls in my "private collection" semen sales. That says a lot about the crowd you do business with. If you do not believe in the premise of the entire red angus breed, I question why you're in the breed.
Accuracies are more important than the actual number, as it "proves" the number. I am always leary of numbers that are backed up by only the owners or promoters of a bull, as those are subject to "variation". Once a bull is widely used, the numbers and accuracy tend to be verified (or not so much). I think we can both remember a bull years back that went from a +1 up to a +6.5 in BW EPD, due to the fact the "owners" were using him exclusively in the beginning. But again, that goes back to doing business with who you know and who you trust. I didn't trust the owners and so I didn't use the bull, even when everyone else was drinking the Kool-Aid and hype from Denver.
As a breeder of red angus, I have always turned in BW's, so I am not sure of your statement that if you do not turn them in they are assigned an EPD. In fact, if you do not turn in information, the registration is on hold, which means it can not be transferred or offspring registered from that animal. It also can not show. I am not sure on embryo calves, but I have always turned those in also and they are recorded in the registration information.
As for pulling calves from a calving easy bull; remember, the bull is less than half of the equation. You have to consider management and heifer retention. Maybe instead of the bull being to blame, maybe it was the heifer that wasn't shaped right or wasn't big enough (calving ease bred heifers do not always make calving ease momma cows), or maybe management wasn't correct. I am not blaming you, because we all have had instances where genetics play games with us, but wanted to point out the equation to a successful calving is more than just bull selection.