I like the idea of a larger "1st" tank as well but realistically that's not going to happen with most new comers. That's just a LOT of investment for a beginner. I think the 75 - 55 is more realistic.
For flow I like a 20x turn over.. this is via the return pump and power heads. I only have experience with Koralias but from my experience I do like them. The "dispersed" flow is very cool and works out great in my 90g.
Have a GREAT day
