Xerneas and Yveltal seem to have mostly positive feedback from fans. I hope they show a new one in corocoro next week. While we can likely expect a small, cute legendary and a 3rd member to pair with the XY duo, I hope they reduce the number of legendaries this time around. Too many weird/forgettable ones from Gen 4 and 5 in my opinion.
Let me rage about some gen 4 legendaries real fast. Gen 4 introduced the most legendaries of any gen.
Uxie, Mesprite, and Azelf - Reduntant. I don't understand why they couldn't have just gone with one creature from a design and story stand point. Will power, knowledge, and emotion is really reaching to me as far as what they are suppose to embody.
Heatran- Rather pointless to the game and a ugly design.
Lunar Duo- I like Darkrai, but think Cresselia is lame and was created solely as a counterpart to Darkrai.
Manaphy and Phione - Pointless, IMO and a waste of an idea. I like Jirachi, Mew, and Celebi, and I personally think they could have came up with better for the guardian of the seas.
Regigigas- Awesome looking, but for all the work it takes to get this guy and his crippling ability, it's useless.