I have been there on a few weekdays this summer. No line (on a weekday) for any coaster ever overflowed its queue. The weekends are another story entirely.
Riddler and Superman are usually the longest lines at about 45 minutes. ***hint*** don't go on Riddler right after the Batman stunt show.
Goliath was around 30 minutes or less, and that was with only 2 trains.
Everything else was between 20 minutes and a walk-on, running 2 trains.
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"X" marks the spot in 2001!