Just a few points to consider:
The sci-fi aspect of the stargate (meaning the effect of that technologically advanced device on humans who use it) is the main theme of SG-1 and SGA. It
can be argued that the stargate is used as something of an after thought in SGU though. That's the difference. Plus most people tuned-in to SGU with the expectation that it would resemble the two shows that came before it. I won't argue the point too vociferously today but just want to remind you that you can't blame people for expecting a show with "Stargate" in the title to resemble the other two shows with that same name. "Stargate" is a label. It's a definition. Like it or not the word "Stargate" was defined (in regards to TV shows) by SG-1 and SGA. To suddenly change that definition is guaranteed to confuse people and turn them off. New Coke/old Coke, blah blah blah.
Yes, SG-1 and SGA were in many ways the same thing. (Incidentally this isn't a bad thing.) I find it funny that you, Yoshi, are so reticent to have someone other than Brad Wright make more Stargate because you fear a deviation from the Stargate you know and love. Well, here you are defending that very action because BW already has changed Stargate. What you feared has already come to pass.
Different characters are fine but there's also nothing wrong with holding onto the familiar archetypes. People like Spock from Star Trek. That character has spawned many clones because people like those character traits. That archetype appeals to viewers. Same with "square-jawed heroes". Most people like heroes, they always have. Granted, there has been an anti-hero movement in evidence for awhile now, but those stories don't generally get the reception that square-jawed hero stories get. Hero-based stories are reliable that's why they're successful.
(There's also the "flawed, everyman-hero" story out there which has seemingly bad guys in the fore that turn out to simply be trying to live their lives as best they can, blah blah blah. It's the new twist on the old "hooker with a heart of gold" story that's been worked to death. I don't know if "Breaking Bad" fits this mold as I haven't watched it yet. I hear it's good and I do like Brian Cranston a lot so I intend to get it on DVD in the future.)
Okay, now back to my dinner!