If you run sufficient LR, and a PH or two, plus a good skimmer, you don't really need the HOB's, IMHO. About all you're REALLY accomplishing with the HOB's is adding flow, unless you have a need for mechanical filtration. IMHO/IME, AC's are just as good as any of the HOB's...we use them when a setup requires a HOB.
Since you don't seem to mind HOB equipment, perhaps you'll consider a HOB overflow and run a sump...you'll like it a lot better in the long run.
What types of fish are you considering? Some are a lot more messy than others.