I am unsure if you are still looking for information, but i'll do my best to answer the main concerns addressed in the two topics.
The first topic you posted has to do with the letter of Cardinal Arinze, which involves the celebration of the liturgy.
The first has to do with the timing of the mass, since each eucharest is the celebration of passover, which occurs in the night between the Saturday-Sunday, the communities celebrate the eucharest after the first vespers on Sunday, which are around 5:00ish pm on Saturday. So liturgically after this period it is considered Sunday, which is why there are Saturday masses after that period. These masses are part of the pastoral of the parish, and so they are open to all the faithful.
The sign of peace has been moved to before the beginning of the offertory, to after the prayers of the faithful in accordance with the gospel regarding seeking forgiveness before going to the altar. This is a change which Benedict has considered for the entire church, (I am unsure where this has gone since then, but it exists.) p§ 49 (note 150)
In my experience, I have never heard parts of the Eucharistic prayer omitted, and the statutes reaffirm the need to follow the approved books for the liturgy.
In the 'Way' there is the introduction of the echoes, this is a chance for the gathered faithfull to express where they see the gospel concretely in their lives. It is very simple for it to sound like an homily when plural pronouns are used as in (we should, instead of I should.)
the sign of communion changed from the letter of Arinze to where it is now. The current, approved, method is for the faithful to stand at their place and then receive the Body/Blood.
The basic question is, is it Legitimate? Yes
It has been approved by the church and granted public juridical personality, and any action (contained within the statutes) are done "In the name of the church."
Now, in terms of your experience, you will have to be the judge of that, as people are different, so are the experiences.