I concur, I arrive the night before for other reasons. For me, even flying 1hr into SNA or LGB (my preferred airports) is somewhat tiring.
Carry bag, TSA, carry bag, board the plan, hoist bag up, sit down, try to stretch, bring bag down, get off plane, walk to rental car, inspect car, drive to DL, find parking, walk to hotel, check in, wait.....oof.
I like coming in late at night, pop into the park (if I can) as the lines are fairly light....sleep, and get in early. Especially now with the ROTR boarding group process. Also, come December, sunset is 4:30-5pm, so usable daylight is limited (but man that park is beautiful at night).
The only time I fly in day-of is if I have a relatively long stay (2 full days), that saves on one night of hotel + cheaper flight if I do Saturday-Tuesday (Sun/Mon being the "full days")