1/2 of your team is pokemon which you cant get in ruby or sapphire
are you playing with item clause on or? if not leftovers became your teams favourite item
For gengar you could go with many different options
for example a special based gengar could be
or a physical gengar would
Sludge Bomb/Thunderbolt [because its special attack is still slightly greater than its physical stats]
for Milotic you could go with Mirror Coat over hypnosis just as a suggestion.
looking at your team your in need of perhaps a heal beller.
To max out a stat it takes 252 EV points so if you want more attack you could remove another 2 EV points from HP and Speed to give you an additional stat point somewhere else.
My only concern is that to get Zangooses swords dance up to sweep you need status inducing moves like for example spore, hypnosis's accuracy is only 60% or so.