If you like taking photos of white columns against a blue sky, Laodikeia is the place to go.
Laodikeia is located on a flat hill and offers panoramic views of the surrounding countryside, as far as to the travertine terraces of Pamukkale. The size of the archaeological site is impressive and gives an idea of the importance of the city during its heyday in the late Roman and early Byzantine periods. At that time, it was the second largest city in the province of Asia after Ephesus. Laodikeia was located on important trade routes and gained its wealth mainly through the production of cotton and the trade in textiles. And its proximity to the thermal springs of Pamukkale certainly contributed to its prosperity.

Laodikeia is really a large area. If you arrive by car, you can drive to the café in the middle of the archaeological site after you have passed the ticket office. Right next to the car park is the eastern end of the ancient street that runs through the former centre of the city. Here you should start your visit. Most of the visible remains are located along the remains of this street: the agora, temples and churches, the central baths etc. And all the white columns mentioned at the beginning (the photo shows the re-errected corner columns of Temple A).  
The best-known building is also located in the central district: an Early Christian Basilica from the 4th century. It was only discovered in 2010 and has been open to visitors for a few years now. Most remarkable are the remains of the floor mosaics.

The T-List entry on the WHC website provides a detailed listing of the type and number of remains. In particular, the fact that there were two theatres, the largest stadium in Anatolia and extensive bath complexes is seen as evidence of the size and importance of Ancient Laodikeia.
The restoration of the Western Theatre was recently completed (in 2022). Carlo Sarion has a link in his review below where you can see photos from before and after the restoration. Now the theatre is open to visitors, you can walk down half of the rows of seats. Construction work on the stage is still ongoing and it seems it is planned to use it as a theatre again in the future.

The Stadium is located on the edge of the archaeological site. It may be one of the largest of its kind, but the remains are little more than a pit in the ground. Only a few rows of stones have survived, most have lost their original position or have disappeared completely and been used for other purposes. There is actually not much to see in the entire southern and western part of the site. From the visible remains, you hardly get an impression of the structure of the city and the large bath complexes. But you get an idea of what might still be hidden underground, waiting to be discovered. You have to bear in mind that modern excavations and research only began in 2003 and are still ongoing. And the nearby tourist hotspot Hierapolis-Pamukkale is certainly the trigger to make the site more attractive for visitors. I wouldn't be surprised if Laodikeia is nominated for inscription in the near future. There is certainly a reasonable chance for success.

If you are short on time, one hour should be enough to visit the central area and the Western Theatre. To explore the entire archaeological site, it takes considerably more time. I spent about three hours there in total. In the warm season (my visit was in May 2024), the blue sky in my photo also means that you are constantly exposed to the sun, there are hardly any shady spots there, actually none at all.

With 21 sites, Turkey is certainly underrepresented on the World Heritage List. But there are already several archaeological sites from the Roman province of Asia on the list. And the remains of Laodikeia cannot compete with Ephesus, Aphrodisias or Hierapolis-Pamukkale. Hence a thumbs down from me at the current stage.

All in all, I enjoyed my visit very much. When exploring the outer areas, I had the site to myself, I like that. But I missed the unique selling point, the special feature that makes Laodikeia different from other archaeological sites already inscribed. So, what stays in my memory most of all are the white columns and the blue sky.