We didn't need Star Wars Land for all the rumors you just listed.
SWL inside of Disneyland park isn't addressing a need other than it was going somewhere.
Back when it was being designed exclusive to Disneyland, it was going into the eastern plot occupied by some of Tomorrowland (lagoon, Autopia, and some of Tomorrowland proper), or it was going into Toon Town until ambition increased bit more, it was never going to go into DCA (not really discussed in earnest at any point along the way); but, in theory - it could have; but, then what to do with Marvel became a bigger problem. Going into a 3rd gate was and is always a possibility as by design SWL is leaving doors wide open for more SWL down the road. The Tomorrowland option under consideration would've limited those growth options. SW in the parks can grow in the future by design if/when they want as you are only visiting 1 location in the SW galaxy with this expansion.
The need to put SWL in Disneyland isn't addressing any specific needs for Disneyland other than satisfying the continued need to grow and evolve and satisfy its guests.
The need for Disney Parks is to get more Star Wars into the parks. It was going somewhere in California.
Of all the options (minus holding out for a 3rd gate), the current plan is being done in the least intrusive way possible. It leaves Tomorrowland intact (and it will allow it to stay Tomorrowland into the future), it allows Toon Town to be repurposed into more "true" Disney IP in an expanded Fantasyland, it keeps Marvel next door at DCA which is a better fit for everyone. SW is set in a more fantasy non-reality universe than Marvel and it's reality (the world of today) that should always be kept out of Disneyland proper. Yesterday, tomorrow, and fantasy are welcome inside the berm - it says so right on the plaque.
Look, I wasn't pleased about where and what was happening either when I heard about the shift to the west and away from Toon Town. My friends that told me they weren't either at first. Once more information became available, the less and less concerned I've become. The only concerns I have now are about the canoes and both ships on route together and the millions of happy guests that will be waving their light sabers around for years to come and how all those extra bodies are going to fit.
It will be a good fit eventually. It's just a bumpy road to get there.