Help a guy out? Renovating home theater system after 10 years and have a few questions.

For the OP, why not get separates for electronics?  Get a nice powerful multichannel amp that will really make the speakers you use sing before you decide to replace them, and add a processor that will do all the new things that your present pre amp section can’t do. Then as technology changes you can change the pre amp but leave the power amp in place

OLED is the latest screen technology and it every bit as good as plasma but has far better resolution than plasma every achieved. My TV is the LG 4K OLED 65 inch and the quality is stunning. I checked it with professional photos on a memory stick and it has superb colors without any if the horrible backlighting of LED or LCD - superbly accurate.

Actually I believe QLED is the latest technology (in the case of Samsung, OLED in the case of LG). As to horrible backlighting of LED/LCD, this isn’t necessarily the case. For instance, consider my (pro calibrated) Samsung UN65KS9800. It features Full Array Local Dimming (FALD) and is every bit as black as any OLED I’ve seen. In fact I’m pretty sure even test/bench measurements indicate it can be a matter of splitting hairs. And, of course you realize that should you need the television in a particularly bright environment, OLED would not be your solution.

gdhal,

    Technically, I believe you're correct that Samsung's QLED is the most recent technology.  IMO, however, OLED is the much more impressive technology.  The  latest 65" LG and 65" Sony (which uses an LG panel) 4K  with active HDR models clearly offer the superior picture quality.  
     Don't get me wrong,  I think your Samsung 65" QLED offers probably the best picture quality of any 4K  LED/LCD FALD hdtv on the market and Samsung's new QLED  technology could be the reason why.  But OLED panels, especially with the 4K and HDR improvements, are definitely superior.  Just view both and compare off axis picture qualities; the OLEDs pq will remain consistently unaltered as off axis viewing angle is increased while the QLED's pq will fade in brightness and resolution as off axis viewing angle is increased. 
      OLED also offers superior color, resolution and black levels since each of the multi-million pixels on a 65" OLED panel are controlled individually and emit their own light intensity and color while also being capable of being completely turned off for ideal black levels.  Samsung's QLED uses backlighting which is less precise although the FALD technology likely helps.

     For years, Value Electronics has been conducting an annual hdtv shootout in Scarsdale, NY which consists of a panel of professional video reviewers and calibrators comparing the top hdtvs and then voting on which is best.
     The OP's  60" Pioneer plasma, if it's a Pioneer Elite Kuro model, was considered by these experts to be the finest hdtv for years in the early years of this competition.
     In 2013, the 65" Panasonic VT60 plasma (with the hiring of many former Kuro engineers and in Panasonic's final year of plasma production) became the first hdtv to top the Kuros in the shootout..  This is my current tv that I've owned for the last 4 yrs.
     LG OLED hdtvs have won the top award at this competition each of the last 4 years (2014-2017).
    The only hdtvs I've seen in person that I would consider replacing my Panasonic plasma with are the LG and Sony OLEDs.
     gdhal, my intention is not to offend you but to give the OP the most complete and accurate information as possible so he can make an informed decision. Him believing that Samsung QLED technology  provides in-home pq that is similar or even within the same class as the pq that OLED  technology provides is just not accurate.
 
 Tim

As for a good cutoff point in past models, it really depends what you want the new receiver to be able to do. Your planned new TV is 4K & has HDR so you definitely want something with 4K upscaling/passthru & HDR capabilities.

You mentioned your boys love sounds flying overhead, but do you have or intend to add atmos speakers (in-ceiling or upfiring)? That will definitely improve those effects, but isn’t an option for everyone due to room and other limitations. If you want to add atmos, even if in the next few years, then you should get a receiver that is capable of it. If additional atmos speakers aren’t ever going to be added then don’t worry about having the ability to process atmos formats.

Streaming capabilities, multi-room audio, and the dozens of other features may or may not appeal to you, but those type of features can easily be added while video and audio processing are the real bread & butter things where you get what the receiver has and have more trouble working around or adding if it’s missing. Aside from getting 4K, HDR, & atmos (if desired), get the most power output you can afford.

As for if the speakers make sense, if you don’t like the sound then they might not be for you. I haven’t heard your speakers, but bigger towers tend to have more oomph than wall-mountable...that said, your room or your significant other might require in/on-wall speakers and nothing you can do about that.

     I really wish the OP would give some feedback on budget and goals since I know of a method he can build his own system using separates that will outperform any available A/V receivers as long as Atmos is not required.

     It's similar to mahler123's suggestion but with a twist.

     vasubandu, you still out there?
Tim