While not without its own flaws, I do feel the SP element of Halo is superior to the SP in Halo 2 / 3.

It seems to me that with each iteration the focus swung more and more to MP and away from SP, with a resulting lack of focus.

I think Halo 2 was most epic in scale. And this is why it suffered. Playing as convenant. Having flood and covenant battle at the same time you battle them...etc.
the campaign jsut didn't have the focus Halo 1 or Halo 3 had.

Halo 1 I think is most groudbreaking but Halo 3 is the funnest to play. Doesn't drag like part 1 in the middle or part 2 towards the end.

wrong forum. Try microsoft or gaming. Thanks.

I agree with you. While I love multiplayer, the real value of a game to me is in the campaign mode.