Well, 10 warriors, 10 wyches, a raider and an incubi clocks in at 310 points with no upgrades. So you are either going to have to go mad on toys, grab hold of some more models, or ask your opponent to scale his list back!
Another alternative would be to use some proxy models if you and your opponent are ok with that. For example if your SW opponent has a couple of landspeeders you could proxy those as venoms.
Put 2 5 man warrior squads on the venoms, 9 wyches plus archon on the raider (with a dizzie) and the list looks a lot stronger. Still got some 40 odd points for toys on the archon, etc.