back on topic.
Slot system was designed to end most hybrids. An archer shouldn't be able to fire at me with a massive bow and then pull out a massive flamberg to fight on nearly even grounds against me. The system works well.
You can still hybridize fairly well. I'm currently running a spartan build: 1h/shield/throwing. The only issue I have with it is the amount of points I have to sink into throwing wpf and power throw to only get 4 throwing spears. I have also played as a crossbow/polearm hybrid where I had 8PS, 125 wpf in crossbow, and 125 wpf in polearm. I would use an arbalest and a quarter staff. I had the option of using a 1 slot crossbow and a beefier polearm if I so chose.
Other than throwing, the slot system is great. It makes hybrid characters just that, hybrids. They can have the best ranged or best melee weapon, but they have to sacrifice ammo and/or take a lower tier weapon.