nice team i think you should get rid of the marill for golduck or an other good water pokemon and that is a good idea to change ember get fire blast or flamethrower groudon get rid of rest for earthquake add a dragon pokemon because they are hard to beat unless you are battling a ice or dragon and here are the too best
bagon ev.30 - shelgon ev.50 - salamence full ev.
and
trapinch ev.35 - vibrava ev.45 - flygon full ev.