What are dynamic events? I thought they were the hearts.
As far as the difficulty in general, I thought things were nicely challenging, especially if you're under the level you should be for the area. It seemed like I would constantly be just under the level of the area when I only played PvE, and I'd even get some warnings on missions that it wasn't recommended at my level.
But once I played WvW for a while and gained a bunch of levels and much better equipment, I was finding those same PvE areas to be a pushover, despite the fact that it's supposed to bring your level down to match the area. I think there must be some bonuses that stay, like perhaps it lowers your vitality (health), toughness (defense), and all those other stats, but keeps the stats on your equipment?