Congrats on paying off the loans! And I think it’s awesome you’ve decided to reward yourself with a nice HT system — what a great gift that will keep on giving so much enjoyment to you and your family.
So, yeah, I have some very specific recommendations for very specific reasons. First, consider going with the SVS speaker system instead of Klipsch. The main reason — the center speaker. IMHO the center and sub will largely dictate your level of ultimate enjoyment of your HT system. The center speaker in the SVS system is outstanding, and notice the design where the tweeter is located above the dedicated midrange driver. The two important things there are that there is a dedicated midrange driver, and using this design will do a much better job ensuring even dispersion of sound for people sitting off center.
https://www.svsound.com/products/prime-tower-surround-system
I’d highly suggest adding the best SVS sub you can afford. If you can stretch a little to add the SB2000, which I have BTW, I think you’ll be much happier in the long run. Check out the SVS Outlet area and you’ll find some good deals.
Now, on to the AVR. My favorite is Yamaha as they tend to sound a bit better and offer rock solid reliability. Plus, for the same price as the Denon you can upgrade to a 100Wpc Yammy through Accessories4less — a highly reputable site — that can save you $$$ (retails for $999 and you can get it for $599). I’d highly recommend this if it offers the features you need...
Sorry if I seem a bit preachy or overly opinionated, but I think the above system would be vastly superior to your Klipsch/Denon option. Anyway, hope this helps and FWIW. Best of luck.