I'm not sure Adoulin and Whitegate make much sense. /yell is typically used for content only (or at least best) accessible from the Middle Lands, like Abyssea and Voidwatch. Unless you plan on also adding cruor-based teleporting NPCs to those areas, this won't accomplish /yell's objective of alleviating Jeuno congestion.
The Chocobo Circuit makes a bit more sense, but what keeps that area (which connects directly to all the major nations) from being the premier area for /shouting is a lack of an Auction House, which adding /yell won't fix.
I also just want to reiterate my opinion that /yell feels like a kludge regardless and we need a more elegant solution for recruiting party members.