The first point... yes, but you mistake why. The greatest problem is that everyone who has been helming the Star Trek franchise has been someone who wanted to make Star Trek 'different'.
Star Trek was never intended to be 'different', it was intended to be 'better', which is different in and of itself, but not just for the sake of being different.
Ever sit down and really just watch the extra features on the TNG disks? They explain the reasoning behind some of the best episodes. You have scores of stories told by people who 'had this meeting with Gene Rodenberry', and came out understanding what he intended Star Trek to be. Star Trek was supposed to be a portrayal of the best of humanity. What can be achieved if we set everything else that is holding us back aside.
For years now, recent Star Trek has been escapism to the holodeck, as you even alluded to. Well, at one time they were going to make an episode about a kid in the future using the holodeck to recreate his lost mother so he wouldn't have to mourn her. The chief writer goes in to talk to Gene and Gene tells him why the script was rejected... "In the future, children wouldn't mourn the passing of their parents as death would be considered a part of life."
It was a way of thinking that they just didn't grasp until they talked to him, and it is apparent that they don't grasp it now.
And now for point 3… because YOU don’t get it either. More mature, more graphic. Know what? That’s just like every other sci-fi series out there, and that is not what Star Trek was ever supposed to be. No, instead that is what they tried to do (to some degree) with the last bit of Voyager and with Enterprise in their efforts to make Star Trek ‘different’. And what ended up happening?
Star Trek was supposed to be the best of humanity, and was enjoyed in large part as a show that was good for families to get together and watch. You do that and I know a ton of families that are hardcore Star Trek fans who will turn the series off. In fact, that is why I never bothered with Enterprise, because they seemed to dwell on trying to introduce mature content. Every other episode was advertised based on some sexual angle. It was as if the writers just couldn’t think of anything other than how sex would work in space. Sure this type of situation was handled in the first two series, but it wasn’t dwelt upon.
It should be noted that some of the finest television shows may be found on cable stations, but aren’t some of the finest because of their content but instead despite it, simply because they have good writers. No, if they go that route, like you said, they cut their audience in a huge way and that just doesn’t make sense to do.
But that brings us to the other point… yes, good talent is needed. But not yet another person who wants to make Star Trek ‘different’ or ‘edgy’, but someone who understands what Star Trek was supposed to be, someone who wants to depict the best of humanity. Someone who understands that we are better than that, better than having to resort to ‘different’ and ‘edgy’ for the sole purpose of appealing to our baser natures.
Then again maybe too many viewers are too interested in appealing to hedonism for us to have TV like that anymore.
Oh, and yes, DS9 was excellent... but it wasn't really Star Trek, it was Babylon 5. Yes, they started releasing their episodes earlier, but after Michael Straczynski had shopped the Babylon 5 'bible' to Paramount, hoping that they would pick up the series several years beforehand. Unfortunately that happened just before Paramount needed something to fill the gap after TNG, so when they started kicking around ideas for the next Star Trek, they just put together what they remembered of the Babylon 5 idea that was shopped to them, adapted it for the Star Trek universe, and started filming.