Descriptions of the concepts:
Concept: Anti-Hax
Analysis: Hax is something that everyone and their mother complains about. It ruins what could be good games, a freeze comes in, Jirachi flinches through three of your Pokemon, a miss decides the game or a crit turns the entire tide of a match-up, or possibly TWave decides that you really need to stay para'd while your opponent gets a +6/+6 DDMence. Why not have a Pokemon that you could switch into all this oncoming hax and prevent it from ever happening? Something that could absorb that TWave, and stop flinch fests, or prevent moves from missing? This would take an extremely complicated combination of moves, stats, and abilities, but if done right this could be exactly what the metagame is looking for.
Concept: Sunnyside Up
Analysis: Face it. Sunny Day sucks in the OU metagame. Sandstorm has Tyranitar, and benefits a bunch of appropriate Pokemon. Hail has Abomasnow and to a lesser extent Walrein, Froslass, and Mamoswine. Rain became a dominant force by Kingdra itself, and not only that but there are more viable sweepers under the Rain such as Kabutops and Ludicolo, etc. The problem with Sunny Day is that the benefits are just too wrongly distributed. Grass-types who through Cholorphyll benefit the most from Sunny Day and Solarbeam are absolutely murdered by the 50% boost in Fire-type attacks. The Fire-type Pokemon who enjoy the said boost will also gain a 50% resistance to Water-type attacks, but lack the Speed increase. How could we craft such a Pokemon so that it gains the benefits of Sunny Day, while keeping it viable in the metagame?
Extra: Taking note, this is basically a "Kingdra in the Sun" concept. A Pokemon who through typing, ability, and stats would be able to fully abuse the weather and benefits of Sunny Day.