I think the only two questions are these...

1. Was the film darker than Disney wanted?

2. Are they therefore trying to tone it down?

The only real way to know is to get Edwards to talk.

My assumption would be that, based on the huge financial success of TFA, Disney execs believe that Abrams' formula is the best model to make money. I think that if TFA's box office had been less significant, the standalone films would have had more autonomy to 'push the form'. Now it could be that Edwards film is just crap and they feel the need to intervene... but all things being equal (if we are to assume Disney have indeed dictated some changes), I'd go with the former and not the latter explanation...

I think this is prove that the sale to Disney was just asking for trouble. I didnt care for TFA and after repeated viewings at home it really didn't fair too well IMO of course.

I think not letting the Anthology SW movies be what the director may envision is a mistake. Thats exactly why they are making them or should make them: To take risks. But ok ok. Im not that naive. This isn't the area of '77 film making anymore. I dont see how a darker, more serious SW isn't a good thing. We really didn't have that yet and the money is already a sure thing since its a SW movie. To force the EP7 vibes onto it is my opinion a mistake but like you said, we need to hear it from the director himself. Everything else is still speculation. I cant believe that this movie is already coming in 6 months. Crazy.

Again, the idea that Disney is watering down Rogue One is nothing but a silly rumor. There is no proof whatsoever that Rogue One isn't going to be as originally envisioned. Read the new EW articles and interviews.

All major films go through reshoots. It's not a big deal. At all.

And many films are lessened by the intervention of execs. I believe there's enough evidence to suggest the hand of others here, as opposed to Edwards' natural schedule for 'pickups' (as opposed to reshoots). To what extent this affects the film remains to be seen, but I see little sense in denying the intervention of the 'studio'.