Magical attacks can never attack the trainer directly, so players would rely on physical attacks. Faster speed magimons would def. help in this strategy, however, it only works if your magimon levels are higher than the opponent's magimon levels. Lower level magimons would likely attack the present opponent's magimons with higher level, leaving the trainer's life points untouched. It all comes down to your magimon's level and if you can afford the fourth skill plus the luck of drawing the effective skills to your alliance.
Skills like wind seal or water seal etc etc, those skills have more chances of working against lower level magimons, they are almost useless against higher level monsters, so keep that in mind as well.
Either way, there is no such thing as the best combo, each opponent requires diffferent approach is all