The difference I see is the number of feats available. I also like this kind of abilities, but I think we need more Terrain feats.
If you just count total feats there are 24 Pathfinder feats (B/M/S across 8 terrain) which is a pretty significant number.
Having said that, I have no real disagreement as the argument that Pathfinder B/M/S is 24 feats seems thin even to me.
Plus, I am all for more feats of any kind.
One question related to this, can you share a mastery or supremacy feat to someone who has not the basics one? And, if not, that's also good for coordinated attack feat chain or even for any feat with another one as a prerequisite?
No, you can only share a feat with someone who meets the prerequisites (in this case the Basics feat). However, one temporary feat can meet the prerequisites for another, so that, for example, with two scouts, one could share the Basics and a second share the Mastery feat (See the rules on Temporary Feats on p. 84 for full details.)
Speaking of temporary feats, I just realized that a Scout (or Captain or Keeper) could take the Feat Training favor and then share the feat with the rest of the party.
So if a party discovered an artifact they were searching for rests in a temple that sank beneath the waves centuries ago, the Scout could get Pathfinder Basics (Aquatic) for 10 reputation and then give it to the rest of the party when they begin the watery excursion.