if U have budget to blow on 4-7k on just AVR sure go for it.
https://av1group.com.sg/collections/arcam
note they are not HDMI 2.1 yet.
if U just want to do 5.1 a AVR10 will do. Don't know how much is upgrade to HDMI 2.1.
issue with Dirac, if you are not technical its a pain to configure the system.
Denon or Yamaha is easier. Denon room correction algo is more complex than Yamaha.
ppl sold their Arcam for Denon just because dirac is not user friendly.
if bluray player. not sure if you can get Panasonic DP-UB9000 but Pioneer UDP-LX500 is $1.5k. IPUK also good, reading around it state its a OPPO clone.
speakers can get very expensive fast! Wilson cost alot, Revel Performa is like $8K for tower speakers alone. too many choice out there too. dont blow all your budget on AVR.
if you plan on doing a 5.2.4 then look for a AVR which supports that now. if you don't mind separates the like me get a separate Amp to power your atmos.
this year not a good year to upgrade. parts hard to find a pricing all high. denon and marantz all have trouble getting parts today.
enjoy your hunt!