I would say Jodah, the Unifier or Dihada, Binder of Wills are probably the right spots for it, and Kethis, the Hidden Hand isnt far behind it on that list, though Flowering doesnt benefit from the cost reduction
Check for the blue card core visible under light
EDH is a huge format, so that increasingly seems to be untrue
A lot of players are less interested in raw muscle or perfect efficiency and more interested in maximizing flavor or developing strange new strategies
The last ability of Clive's Hideaway will allow you to cast both exiled cards without paying their mana costs (assuming you control four or more legendary creatures at that time.) In a Two-Headed Giant game, Traveling Chocobo's second ability does not affect triggered abilities of permanents your teammate controls
Either of these sounds like the kind of deck for me, so what might keep me from playing them