Help with new 190 gal build

[coralor]

I don't have any drawings yet, and admittedly I wouldn't know how to add them to the post. I can try and learn, though)
What if I did go with 2 drains and 2 returns, would a Fluval Sea SP4 pump be sufficient in your opinion? I've heard they are decently priced and quiet.
Also, how long and thick should the overflow be? I'd like to place a power head on each side. (Not sure how to incorporate something like a gyro or MP40 there).