I would hold on all of those guys. You've got some pretty high standards for slow starts . JVR for example is on a 64pt pace which would be a career high.
The other 3 aren't doing that bad either. Currently on ~50-55pt paces which probably won't continue seeing as how their shooting percentages are quite low right now. Hoffman's had a slower start for sure but he's around half of his career shooting %. That won't last.
The only guy on that list that I would maybe make a move for is Ehlers for Hoffman. You league doesn't count SOG so that lowers Hoffman's value. Ehlers has dual wing eligibility and he probably out-points Hoff this year with how that jets' top line is rolling.
O'Reilly and Monahan would normally be interesting as well but O'Reilly's nagging groin injury may slow him down this year and Monahan only has C-eligibility where you're pretty set already.
If your team is off to a 3-0 start with these guys not performing at their peak levels then why change anything when they're bound to bounce back?