This I would be on board with. Why do I need different skills in the first place? Why not direct upgrade skills and traits?
If someone is overwhelmed with the current buttons, I would be ok with an Option to consolidate buttons. I would not be ok with it being forced on me.
As far as the OP goes
"Rdm: 1. Corps-a-corps/displacement merged replaces one after it is used
2. Tether removed nigh useless "
I can see the case for #2 but am very against #1. There are times I want to use displacement before corps a corps. I would dislike having this option taken away.