Beginner home theater setup questions...

BIG congrats on paying off your student loans. I also paid off my student loans earlier this year - such a huge relief, but lots of work (always had two side hustles).

I like the idea of the Denon receiver, SVS sub and OLED, especially right now since LG finally has some competition which has begun to drive down the price of those panels. Klipsch seems to be the default for HT systems. Unsure (from lack of knowledge) if there are alternatives that can better the Reference Premiers at the price range. If size isn’t an issue, you’re really looking at value, and you can spend just a little more on a sub, I’d take a look at HSU. Question: What do you mean by piecing together “from a various sources.” If it means what it think it means, then I would stick with the same manufacturer and model with the speakers.

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...

https://www.accessories4less.com/make-a-store/item/yamrxa2a-rb/yamaha-rx-a2a-7.2-ch-x-100-watts-a/v-receiver/1.html

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.

Hard to go too wrong with your HT setup. You could spend a lot more than the SVS speakers that @Soix recommended or the Klipsch and not realize much extra enjoyment in an HT setup. I am inclined to agree, though I have not heard them, that the SVS center will be a better performer than the Klipsch.  But, the SVS are lower in sensitivity than Klipsch by a good margin. So it will tax the AVR a bit more, so more power would be a good thing. If I was using this setup for both movies and music, I would side with the SVS. Also, accessories4less caries Denon receivers as well as Yamaha. You could get theAVR-X2700H for less than the x1700 at BB. 

Congradulations! A big deal. My partner and I met in graduate school 36 years ago. We put together an increasingly good Home Theater for us, while I put together an increasingly good audio system for me. You can see the systems u der my UserID.

You want all the same HT speakers… the quality is not nearly as important as they are in audio. But the same voicing is critical. Definitely a good OLED TV. We researched the daylights out of the subject and concluded a High end Sony was very worth it. For us the TV is a minor expense…. Audio portion… maybe $35K and monitor $5K. The Sony OLED very worth it… we bought a regular 65” for the bedroom and 78” for the home theater… Both were replaced under warentee. The OLED has a 18 month warentee… good thing… it pooped out after 16 months. The 65“ died in 10 months so got replaced under the 12 month warrantee. Sony has the highest quality rating… I would spend the extra.

I add my congratulations to paying off the loan.  I probably shouldn't opine hear, since I haven't heard the specific speakers that you are discussing, but a few thoughts.

1) In general, I think a set from the same manufacturer works better than a mishmash of different companies.  I have 2 HT systems in my house.  One has a speaker smorgasbord, the other all from one manufacturer.  I definitely prefer one from a single manufacturer (the AVR in the two is the same, more later), as one can actually hear not subtle timbre mismatches when playing music in the other one.  For video content this is less important.

2) I don't know if Denon is using room correction software in their AVRs, but I use Anthem AVR, with their Anthem RC, and this has made a big difference in both systems, particularly in the bass.  If you don't like RC you can disable it, but I think it is a valuable feature