Connecting through PEK or PVG, on your outbound, you can get away with 2 hours. The infamous China delays tend to affect outbound Int'l traffic far moreso than inbound, so if it's a delay-prone day due to "special circumstances", you'll likely get in fine, and then your outbound will be delayed a few hours. Even if you misconnect, there's lots of service to BKK where you can be reaccommodated.

On your return, you'll want to leave more time. There are many fewer flights ex-China to US Mainland, so if you misconnect, you're much more deeply screwed...

You can leave less time in HKG. I've connected through HKG on layovers as short as 65 minutes several times with no problem. Just make sure you have a boarding pass for your connecting flight so you can go straight to re-clear security, instead of having to noodle around at a transfer desk.

Consider NRT or ICN as connection points too - I've found them both to be much more reliable and convenient than any mainland China airport for connections to SE Asia.