I'd argue they don't. Shifters are either extant ancestral precursors of were-creatures, or a genetic melange of the various Therianthropes. Neither suggests needing to stick to one kind of shift.
I hope they ditch the idea of Shifter lineages, without the stat bumps they're pretty much pointless. Just put all the Shifts into the same pot, like the Aasimar's Celestial Revelations..
Yeah, that's where I'm at. I'd like to see the species prerequisites, with a sidebar on the DM waiving it for story reasons. This only serves to make the DM "the bad guy" if he wants to play a traditional Eberron game. On the other hand, the DM gets to be "the good guy" if he allows dragonmarks...
The Cartographer is an interesting idea, glad to see them embracing the tool using object oriented magic idea, instead of keeping them in a psuedo-steampunk ghetto.
The dragonmark feats are trash. They need a species prerequisite, and "pay walling" some of the abilities behind taking a...
And the clause in the ORC about reserved materials specifically address intellectual property in the public domain:
Reserved Material means trademarks, trade dress, and creative expressions that are not essential to, or can be varied without altering, the ideas or methods of operation of a game...
The captiue men of strength I gaue to you,
The weaker sold; and this y’all know is true,
The free-borne women ransom’d, or set free
For pittie sake, the seruile sort had yee.
The Faire Æthiopian, William Lisle 1631
;)