What is the speaker setup? 5.1? An atmos capable receiver wouldn't add much unless you plan on an atmos speaker arrangement. There are a few options to choose from with your current setup. Given the same gear, I'd connect everything to the TV and use an optical cable to the receiver. That model Samsung TV should still have the DTS Neo 2:5 feature. If equipped, it can convert all of the audio input to it and output it to the receiver in DTS 5.1. ARC will let you pass DD+ to the receiver but you will have to turn on HDMI-CEC in the TV and receiver. Samsung calls it "Anynet+" and it needs to be on for ARC to work. HDMI-CEC and ARC can be headaches and many opt for the optical cable connection. Not much is lost from DD+ to DD with an optical connection. If you decide you want lossless Dolby TrueHD or DTS HD Master Audio from a 4K disc player, just get one with two HDMI outputs and send the video directly to the TV and the audio directly to your receiver.