>>2832101 (OP)
Been in January this year, so your experience may vary since it was hardly crowded by then.
>Forbidden City
Didn't have to book shit. Just go around the moat and you'll end up behind Tiananmen at the ticket office. Walk up, buy the ticket and go in. Might be a good idea to do this early in the day since they probably have visitor limits.
>National Museum
Haven't been, but I went to check out Mao's corpse and the square. I feigned ignorance to a checkpoint guard before I went to the Forbidden City and he was kind enough to book me a slot for the next day at 11AM through his Weixin.
DO NOT do anything that requires an entry ticket on weekends by the way. Weekends are of the devil.
>>2832126
I connected a Revolut card to AliPay and had no issues once I got past verification (which admittedly shat itself and some chink had to flip the switch manually which took two days). Other than that, despite what people online say, everyone in China took cash without grumbling and ATMs charged no fees.