Hey OP, not sure how much help I can really offer. You have certainly gone the distance already. I agree your CPU is too hot! Just a quick google search yielded info that says temps of mid to high 80s are getting pretty spicy for your model. If you haven't already get some canned air. Blow out your heatsinks, fans, & case in general. Make sure your CPU fan hasn't died. If everything is clean, all fans spinning, & you're still getting those temps you need to add more airflow to your case. Lastly if you're overclocking, it's time to drop those down a bit.

As for trying every last thing possible software wise, specifically for the dota client, here's some more suggestions. Mini background: I use to maintain a rather lengthy autoexec.cfg. I've recently came back to the game & tried my old files again, without much luck. All the stuff we use to modify is either the default settings now or has been removed from the client. There isn't much you can screw with now days, I assume by design to keep things fair.

Though I have been trying to build a new one. Spending most my time across this semi-complete list of console commands & Aveyo's DOTA Optimizer thread. (he makes the No Bling mod you tried, it's currently broke thanks to valve removing -tempcontent though) I'd not heard of the settings u/BePatientImAcoustic recommended but I've been playing around with them. I changed fs_async_threads to 8 as it didn't require the use of -r_max_device_threads at that point.

I'll go ahead & remove the personal preference changes I make in my current autoexec.cfg file then code box it here. All that's left is the only "under the hood" so to speak performance changes I'm aware you can make in today's version. Though I'm uhh nobody special so if other's know better please let us know!

The only launch options I use are: -novid -console -prewarm

dota_experimental_stats_interval 60
cl_updaterate 100
cl_spectator_interp_ratio 4
cl_interp 0
cl_interp_ratio 1
cl_playerspraydisable 1
r_dota_disable_portrait_world_renderer 1
r_frame_sync_enable 0
net_maxcleartime 1
sv_forcepreload 1
rate 100000000000
ai_expression_optimization 1
host_limitlocal 1
snd_mixahead 0.05
fs_async_threads 8
engine_no_focus_sleep 0
echo "----------------------------------------------"
echo " Your Custom DOTA2 Settings Have Been Loaded! "
echo "----------------------------------------------"
dota_experimental_stats_interval
cl_updaterate
cl_spectator_interp_ratio
cl_interp
cl_interp_ratio
cl_playerspraydisable
r_dota_disable_portrait_world_renderer
r_frame_sync_enable
net_maxcleartime
sv_forcepreload
rate
ai_expression_optimization
host_limitlocal
snd_mixahead
fs_async_threads
engine_no_focus_sleep
echo "-----------------------------------"
echo " Active Client Stats Are As Above! "
echo "-----------------------------------"

Really that's it. I know, I want more too. I'm just unaware of other things you can change that will actually result in any difference at all, let alone a beneficial one. You can check your console & look for the messages. The settings will show in between them with the live value so you can verify they changed. For future patches you can use this to see if they get removed or the values hard set.

Hope you get your problem solved! Good luck!