It really comes down to what attractions are a priority for you. Getting FPs at major attractions day of can be very difficult, if not downright impossible. In October, we applied a strategy where we sometimes did the first park, other times our second park. Granted, we were there for an extended stay (10 park days) so we had some flexibility (though the hurricane took some of that away).
Here are a couple of example days. Our first day, we did rope drop at MK, with full intention of hopping to Epcot solely for a concert and then to HS for Fantasmic.. We focused on the right hand side of MK that day, doing mid-morning FastPasses for Space Mountain and Pooh, and an early afternoon FP for Mine Train. Immediately after Mine Train, we jumped on the app and scheduled a FP for Fantasmic. We knew we could not get what we wanted for RNR, TOT, or Toy Story at that late date/time, so we had planned to hit those on another day.
By contrast, on our third day, we planned a morning on the left hand side of MK, hitting Jungle Cruise, Pirates, and Splash early before crowds built (Big Thunder was being refurbed). So, on that day we planned our FPs for the afternoon/evening at AK.
On other days we made our decision specifically because of a particular attraction. We had no Epcot mornings scheduled, so on the day we wanted to do Frozen, our FPs were in the second park. By contrast, we prefer HS in the morning, so we scheduled RNR/Toy Story fastpasses (split party for those who did not want to do RNR) on a morning we were at HS. For AK, we made sure and reserved a FP for the evening Safari ride.
In other words, there is no right or wrong answer. It all depends on what attractions are most important to you and when you'll be in those parks. Mine Train and Frozen are examples of attractions where even rope drop does not work well, so they drive your use of FP.