@ahwin- your problem is 100% with the carb. When you opened the carb the refitting it back is not perfect as a result you are suffering from these problems.
The solution for your problem, is re-opening the carb and properly cleaning and re-fitting it properly.

For opening the TPS, just hold the TPS connector and with other hand press the clips on the connectors. A thin screwdriver or a line tester will help. After pinching or pushing the connector, just pull out the connector from thr carb socket. Never and i repeat never open the TPS by its screw from carb. It will be another headache to reset the TPS.
Clean the carb thoroughly and refit back. First fit the air intake side hose first and then fit the engine side hose. tighten it lightly by the clamps.
Then what you do is start the engine and check if choke is jamming or not. Sometimes a slight open choke will create a lot of headache.
For tuning the easiest method is to:-
1. Open the air suction pipe from engine intake.
2. Seal the hole with your finget otherwise bike will not start.
3. turn the mixture screw 1.6 turns out.
4. Start the bike. Make sure engine is warm.
5. Now increase the idle to 2.5 k rpm by idle screw and hear the sound.
6. Now turn out the screw by hearing the sound. No need to look at tacho.
7. Hear the sound and listen where the idle is highest and bike is roaring. Stop there. It will be in between 1.8-2.5 turns out.
8. Now decrease the idle to 1k rpm and leave the finger blocking the air suction pipe. The bike will stop.
9. Re-fit the pipe into the intake manifold and restart the engine and adjust idle to 1k rpm.

IMPORTANT THING TO REMEMBER:-
The steps where i told to open the suction pipe from intake manifold and close the manifold opening with finger is very important as if you do not follow this method then idle will not decrease even after opening the screw more turns out. So most think that tuning a CV carb by old method is difficult. But the right method is to close the air suction and then only tune as by this method after the rpm is highest on further turning idle will decrease and thus you can know. All CV carb must be tuned by this method.

Regarding bike shutting up after high ripping, check your spark plug as a spark plug which is sorted will give the same problem as yours. So check that also.

For the sound of brakes, check the metal strip on the callipers and if they are misplaced as many mechanics mispalceses it and that causes the disc to make the sound.

I don't now about Hunk, but if there is a insulator between carburettor and head intake, then u should check that insulator. As u've done for the first time, you might have fitted in reverse direction. There is 'T' mark written on the either side, that T mark will be on the UP direction. If wrongly T is in down direction, then air leak will happen.

I got it to a Service Center today. My tenant knew the owner of the Service Center, so got some preferential treatment.

The spring on the idling screw was missing, that was causing the fluctuations in the idling. It seems to be fine now, bike doesn't shut off after opening throttle a fair bit either.

So looks like my problem is solved. Thank you all for your time.

Man, you are hilarous. how did the spring got lost. Also how can we know that the spring is lost. Ok, all is well that ends well. Next time before opening anything have a proper look and try to remember all the parts before opening.

the bike feels a little sluggish now. Acceleration isn't as strong as it used to be. Mixture is too rich?

It needs carb re-tuning. Clean the air filter too if not already done.

Here is how to tune


Edit:
Oh you already know that

Yes, my only problem with that method is closing that brass pipe when the engine is hot. :P That brass pipe is also pretty hot. :P

Yes, my only problem with that method is closing that brass pipe when the engine is hot. :P That brass pipe is also pretty hot. :P