It's amazing that someone would continue to rant for three pages after a developer came out and flat-out told them they were wrong. But hey, that's half the fun of the Internet.
I almost never play multiplayer, for a variety of reasons. I, like 99% of the other Sins players, play single-player games. And I'm GLAD we don't have a campaign to play; those tend to be really boring, with almost half of the missions acting as "tutorial" levels to introduce you to a new unit or mechanism (like when it takes you eight levels in a 10-level campaign before you unlock the "big" units). And some of the rest are built around a "gimmick", like no unit replacements or the need to defend a certain structure/unit. I really just don't like that sort of thing, and it really hurts the replayability.
Now, one of the ironies is that multiplayer games are almost always, by design, predicated on balance. Two players, with the same starting resources and such, facing off, usually on a fairly small and symmetric map to keep things short. I, on the other hand, play 10-way wars against Unfair AIs on a 115-planet single-star map with a lot of randomness in the map; it's brutal when you're getting hit by five or six AI fleets at once, each of which is bigger than your best, and where there's a good two or three hours of solid warfare in the midgame. It takes an entirely different set of tactics than a multiplayer match does; there's no point in unit rushes, and it's all about your skill on defense against horrible odds. Entrenchment was a godsend for this sort of playstyle, but Diplomacy sounds like it'll be critical too, as one of the best ways to survive that sort of 10-way war is to make non-aggression treaties with three or four other races (hopefully including one of your two closest neighbors).
The new diplo techs sound interesting, as do the diplomacy ships, but I'm still hoping they'll overhaul the pirates at the same time.