Heyas! I have an Archer C7v2, and love the build! 
Num 1 Comment:
Maybe a bit early right now to adopt this, but some people are working on enabling the Hardware NAT for LEDE: Hardware NAT For LEDE
gwlim is trying to set this up for his WNDR* (mips - 74kc) devices, but it should work on Archer C7 which uses the AR8327N switch (same as the tl-wdr4300). Would just need to configure the switch registers for ISIS to get it working. Can use their ssdk_sh to access the switch register configuration utility. If HWNAT comes to the Archer C7/LEDE, there would be no reason to go back to Original FW vs LEDE!
I do not think it's currently ready, basically someone needs to figure out the ssdk_h commands to enables the registers. blogic in the thread says he has a working qca8k driver which may be comming soon. So yea exciting stuff.
[EDIT: Edited out the quote, just realized when he said "these patches are great", he wasn't talking about that threads patches, but patches the poster did elsewhere.]
Num 1a Comment:
That said, gwlim from that thread has a number of other patch "optimizations" he does for his WDR* devices. You can go to that thread and see his patches listed sequentially. Hardware is very similar to our ArcherC7, and some may work in this threads firmware. His github patches are:
Num 2 Comment:
As for the SHA performance decreases, maybe something to do with the OpenSSH vs Hostapd Internal Crypto stuff? I know OpenSSH has optimised versions for mips, which greatly improve AES performance (for a bit larger binaries). I know you have both installed, so maybe somewhere in the configuration you don't have OpenSSH set for default and it's using the hostadp internal stuff cuz it see's it's installed (I know issues where people had both installed and WPA_SUPPLICANT_INTERNAL in config vs WPA_SUPPLICANT_OPENSSL). Just a thought, I haven't looked into it.
Num 3 Comment:
I see you are using the ath10k-CT firmware (modified qca 10.1.467), over the default original kvalo firmware (original latest qca 10.2.4-1.0). I was just curious on why you choose the -ct ones? Both are updated often (~2.5 months ago). I'm not saying one is better or worst, I was just curious if you choose -ct for a specific reason? Do you get better performance? Did you notice some bug fixes with -ct? Any reason in specific? I haven't tried the -ct firmware, I've been wanting too, to see if it fixes the archer c7v2 crashes with the new QCA61x4A wireless cards under load (dell xps 13 9360, acer swift 3, ect). Just haven't got around to it yet.
Num 4 Comment:
This has everything I need, except my "tor". I use my router to run a tor relay. So you can access .onion websites with a sock5 proxy through ur router when u need to access those sites. Some people also set it up through a hidden SSID, so u can go through ur tor with that. There is no luci module for tor currently though. I also perfer the "luci-theme-material" theme.
Num 5 Comment:
Have you played around with the SQM scripts on the Archer C7v2? I know performance is very specific for certain hardware. It would be nice to know which is best for the Archer C7v2. I know cake is accepted as the general default. Be nice to know if one of the other more unique ones performs better on our hardware.
I extensively tested it a long time ago (~6 months). At this time cake wasn't available, but i tested other scripts "simple.qos" was the default. But what I found is most of them would solve bufferbloat, but limit the upload/download much to much. I found the most simple solution was to install "luci-app-qos", and just manually limit the uplink/downlink. I was able to solve my bufferbloat perfectly and get a much higher uplink and downlink speed with this compared to sqm-qos. Again this was tested way back when, and we never had cake, or piece-of-cake back then. So they weren't tested. On my 50/10 connection (maxes near ~55/~11.5), my bufferbloat gets an A+ with 51.1/9.4, using just the simple luci-app-qos and tweaking it to max out uplink. So have you tested these scripts to see which is the best performance? Or is it just using the default cake currently? I'm fine with sqm-qos, just want to make sure I get the same or better performance compared to the simple-qos tweeked version.
Love the build! Keep up the good work!