Fascinating question! Thank you!
My thoughts (which I’m certainly not wedded to):
There will likely be insufficient fights by the end of day 1 to have properly sorted out the defensive worth of the defenses. My guess is the relationship between true strength and rated worth will still look pretty sketchy.
That said: weak defenses will almost certainly tank fast. Strong defenses will be all over the map. So the risk-adjusted reward for strong defenses will be quite variable. While the risk-adjusted reward for the weak defenses will fall as the day progresses.
My thought, therefore, is jump in quickly and snap up points from the weaker defenses while they’re on offer. I’m confident enough in my ability to eke out wins against the tough defenses that I’ll take that risk in exchange for being able to maximize points against the weak ones.