Fastest way get to the Tower Tycoon beat him and get 20BP, do this over and over again to get the power items (lose after you beat him so that way you only have to win three times to get to him). Also you don't need the PokeRus to EV train it just speeds the process along by doubling the amount of EVs you get from a fight (so that with a power item you get 4X EV points per Pokemon).
Something to consider are the IVs and Natures of your Pokemon. If you don't have good IVs your Pokemon will flounder in the competitive scene. Natures also play a role because with the exception of a few they will lower a stat and raise a stat
http://www.psypokes.com/lab/natures.php, there is a Natures guide.
Hope this helps, also here is something that you can use to calculate your IVs
http://www.psypokes.com/dex/iv.php.