How much power/go-go did I leave on the table?

Hello all - I have finally completed my first engine rebuild with the machine work done by two shops locally (one for the block, one shop for the cylinder heads)

The heads are casting #4027163 http://www.mymopar.com/headcastnumb.htm

1977-86 1.78 1.50

Nothing done to them, except rebuild with seals, etc.

The engine has KB167 030 over pistons, stock rods, and a Comp Cams K-kit K20-223-3

The cam specs are XE268H: full specs here: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=627&sb=0

The car feels great, and night and day difference between the blown out 318 I had in there, probably factory and never rebuilt.

I was using the several articles out there regarding hipo 318 builds. While I am not so concerned with the overall output that these articles were seeking to attain, I was using the tech of the articles in my build.

The common thread to the articles was the heads, some were ported, some switched to Magnum style roller heads, etc. But bottom line, all these 318s had head work done.

My question to the group is: How much did I leave on the table, by not being more aggressive with the specific head stuff during the rebuild?

I suppose I am not looking for a hp/numeric answer, but if it was your car, would you re-do it?