Welcome to the light middle weight league of sorts!

The tank will be perfect for you guys and your clowns will absolutely love the extra swimming room. As you have a pair already, I'm not too sure if you would like to put in at the beginning as I think they will assume the whole tank as their territory and harass your other fish. The lyretail are awesome and Gary does have some really nice small ones that you can watch grow up into the beasts they are. Since my rock is already seeded, with some asternid snails, I would try to keep the wildlife on it for seeding purposes. I love flasher wrasses but be sure to keep at least two males or create a harem for them to keep their colors. Its really tough to get females and I eventually ordered mine from vivid aquariums. I ordered two females for my stud but sadly one of the females died the day before she was supposed to come out of qt.

As for equipment, Lyretails do best when they are fed fairly frequently. In the wild they are constantly being delivered food particles that are swept by the currents at the top of the reef. I would suggest you invest in either the Eheim Autofeeder or since you are planning on getting an Apex, get the Automatic Food Dispenser. I have yet to upgrade my software on my Apex to support the one I have, but I look forward to having the feeder dose food and the Apex telling my Ecotech Pumps to go into Nutrient Transport Mode or Night mode. Such an awesome concept.

Good luck man and post some photos!