For this Team I'll drop Durant, if you want a Steel type you have plenty to choose from since you're playing Y. So I'll suggestion you used Metagross (High D, P-Attack, Decent S-Attack), Steelix (Straight Defense), Aegislash (with stance change), You can even used Scizor which will give you a super attack plus a mega evo. Maybe you like Misamagius, but I would dump her for a Gengar, Alakazam, Espeon something along the line of high s-attack. If you don't want to used Legendaries replacement for Ho-oh- Charizard, Arcanine, Volcanroa, Magmortar. Replacements for Mewtwo, Gardevoir, Gallade, Alakazam, Espeon.