This beautiful building, like most Gaudi designed properties, is well worth a visit. The Palau is quite small (easily doable within an hour) encompassing around 24 rooms/points of interest. Tickets are sold in timed slots, which goes some way towards limiting bods in the building. My visit was in early March, and whilst there were other pesky visitors obstructing my photos, numbers were managed very well in terms of providing an enjoyable experience, and staff were friendly and light touch. You can download an audio guide to your phone, which I did, but on arrival was advised that the physical audio guide was better, and it was indeed excellent - very clear, informative, and user friendly.
It’s worth having a check on the weather forecast ahead of your visit, as rain or strong winds could lead to the rooftop of the Palau being closed off, and it would be a shame to miss that, as it’s one of the highlights.