I am the last person to tell you how to port anything but a while back one of the magazines did an article that followed a set of OEM Mopar heads through 7 different stages of being ported with flow bench testing between the steps.  There were times when eliminating certain "bumps" was actually bad for power.  I believe they said they were either losing "charge" velocity, or that sometimes causing the charge to "swirl" seemed to be good for power too.  I think that for most applications, just porting the heads and intake manifold to match each other is nearly the biggest HP gain of all.
It is one very complicated subject to be sure.

Basically, you want the flow to act jus like you see it "Swirl" down your toilet, yes? And now I see some guys cutting massive grooves in the intake runners and combustion chambers, dont get that, except fuel puddling up and acting like a blanket .  Seems to me like loss of low end power, IDK.

Unless one has a flow bench to quantify the changes they're making and dyno to determine what affects those changes have on the engine, I think that you're pissing into the wind.  The only things worth doing without the means to test the results are a port match and mild cleanup of obvious casting flaws....even then, you've got no idea what your doing without a means to measure your results. 

The correct valve job (which also requires a flow bench and dyno) performed properly (key words) will have a far greater affect on anything than diving into the head with grinders to make it look faster.

There is no single concrete answer.

How much port work costs is not directly proportional to the power gains one might get in return for the work that he paid for, nor is spending an additional 20% on a port job equate to 20% more power than the port job costing 20% less, for example.

The amount if time it takes to port a set of heads will vary by the porting approach deemed most suitable for the intended power output of the engine combination.  Depending on particulars that extend above and beyond the cylinder heads themselves, the hours invested in porting heads for a specific engine might be five hours and it might be fifty hours...or however many hours it takes.

A set of cylinder heads with flow numbers greater across the board than the next set of heads does not necessarily mean that a given engine build will make more power with the heads that have the higher flow numbers (all else being the same inside the engine). In fact, the opposite might even be true where the lesser flowing heads are better suited and the engien makes more power. Flow numbers to not automatically equate to horsepower in-and-of themselves.

"Balance between the intake and exhaust" is something that is most accurately handled by valve timing events and ultimately camshaft selection, not porting; let the porting approach and intake/exhaust port characterisitics be executed best as they are fit for the application and then cam accordlingy off those port designs.

With Ford 385 Series heads, it is not always advisable to execute manifold port matches on either the intake side or the exhaust side.  Every case is diffierent and often the stock entry and/or exit is preferred. Also 429/460 passenger car heads do not have 4 identical intake runners, they are paired and the more power you are shooting for the more this needs to be addressed accordingly.

LO