Yes, Java interaction with Quartz is reasonable and probably should be your default option. I think people are sometimes too indecisive to use Clojure's Java interaction, but it actually works quite well.
To evaluate Quartzite, I would like to take a look at the specific planning functions that you know you will need and see if Quartzite provides interfaces for them.
Another solution developed by my colleague is the native Clojure library: Monotony might be worth checking out.