I don't use 2020 anymore, but when I did, AutoFPS was indispensable. Excellent app, and the developer is responsive and communicates directly here on Avsim and on his github forum. 

6 hours ago, CFIJose said:

1) Run, don't walk, and get your copy of REX Accuseasons. It's a game changer.

2) The FSLTL fleet &  Traffic Injector are free and easy way to have lots of Airliners. Just beautiful!

3) I'm using DX12 BETA and it's what I prefer.

4) AutoFPS is a must try! Also check out FlowEssentials or FlowPro. Must have IMO

I only have Rex Atmos. Is Accuseasons overlapping with the former?

11 hours ago, Bob Scott said:

And if you do decide to use LSFG, it only works with DX12.

Lossless Scaling works with both DX11 and DX12.

14 hours ago, bbsmitz said:

4)  Have any earth shattering add-ons been released?  I know about the basics like addon-linker, we love VFR etc.  I've heard good things about autoFPS which I may try out.  Anything else?

To me recently, the release of Chaseplane has been a pretty big game changer. Other people have made good suggestions though.

 

14 hours ago, bbsmitz said:

2)  Are there any decent AI Traffic solutions or is it still kinda a kludge?  Is AIG still the best option for model matching?

https://flightsim.to/file/42731/aiflow. AIFlow has been great at making AI traffic behave more realistically and is highly configurable. There's also a full blown ATC/Traffic solution called BATC (Still in Early Access) which has it's own custom traffic injection including a real world schedule for parking, schedules etc. It's not perfect, hence the early access, but a good shoe-in for when there's nothing going on in vatsim in a particular location.

Since a couple of months I've just been shutting down 2020 by exiting fullscreen and clicking the the little x at the top right of the window after landing. No going back to the main menu or anything, just I'm outta here, see you tomorrow! Had zero trouble with that, it'd fully shut down, and none of those do you want to start in safe mode pop ups upon starting the next time. 

Since yesterday though I've had a few ctd's. Not sure what's going on, but seems it could be connected to the FSLTL AI traffic generator.

Anyway, one addon I like that seems easy and good for my low end system is the MSI Afterburner together with the Riva Tuner. I'll manually set lower framerates in cruise and higher ones on takeoffs and landings. Works very well for me, and I just set the little GPU temp display, easy to keep an eye on it.

Thanks everyone for your comments!  So far...

1) For the trees gonna go with Rex Accuseason.  Just seems more recently updated.
2)  I found the entire AIG library in a google drive file somewhere so I just downloaded that for the models.  PSXT+RealTraffic sounds really neat, but no sure I want to pay the subscription, so I might mess around with various other injectors and see what works.  Ideally would transition back into Vatsim as soon as I can.

3)  Guess I'll try both DX11 and 12 and see!

4)  I've always been skeptical of frame generation, but may give it a go.  Appreciate all the votes of confidence for AutoFPS.  I have MSI afterburner and did a lot of OC testing when I first got my system, but it'd invariably lead to crashes, so now I just frame limit to 50fps through the nvidia control panel.

Thanks again for all the suggestions!