If you want steers go with Heatwave or Walks Alone. Best shot at getting a great one, and just a good a shot at getting OK calves. But since you have heifers I would not take that route until after they had the second calf.
For heifers I would go with a pure Main or Sim, several have been mentioned.
There are really no bulls out there that can guaranty a great one, pure bred or clubby, go with the favorites and cross your fingers.
If it were me and I had good Angus heifers I would breed for heifers, at least from their first 2 calves, either show or replacements with Main or Sim bulls, on average you will have an easier time selling and get a more consistent product you can move. You have had some good suggestions for Sim I would look at I-80 or some of the other Ali sons for Main bulls to use on your heifers, some have had good luck With Majors Money Man as well.
Find a direction you want to go and then make your choices, shooting for a great steer out of a heifer is probably not the direction I would go.