For that, I suggest hard seat. :p

OP:

There are two of us traveling together (a couple) and we are considering upgrading to this sort of travel by train.

I do not know or speak any of the native languages spoken in china.



A couple, with at least one with no mandarin speaking ability.
Meeting locals on the train?

I could imagine that private cabin could produce a more memorable
experience of train travel in China over a hard seat.

I took one of the overnight D trains last night (reason: I originally bought a ticket on the fast train for tomorrow, decided I wanted to travel earlier, changing the train ticket was easier than refunding it). I shared a 4 person birth with only one other guy, which was nice enough. But, what I wasn't prepared for was that these D trains make ~5 station shops between 9p and midnight now (as opposed to one previously)... still takes 10 hours, so they must be going a little faster. This was rather annoying because every 15 minutes or so, there was a new group of people traipsing through the aisles with their luggage.

As far as chatting with people is concerned, last night's train was 30% foreigners, and I expect this number to increase sharply after tomorrow. Furthermore, all of the Chinese people that approached me were dying to practice their English. I can do without those conversations (been there, done that), but the first time rider might get a kick out of the drill.

You were on a "D" train. Its does go faster, its a "bullet train" CRH, 200 KMH.
Where do you carry on conversations with passengers on an overnight train?

On the Z trains, I used to enjoy hanging out the dining cars because some of them were uniquely decorated and the atmosphere was just plain interesting. However, the D train dining cars (at least the ones I've seen) are more reminiscent of the cafeterias in local office buildings---> I don't go there, but if I was really in the mood to meet other people, that would be a logical choice.

Apart from that, I often end up in a room with 3 other strangers, who invariably want to talk to me. I usually play along for a bit before moving to the stool in the aisle outside of the room with my computer and/or reading material.

I rarely sleep before midnight anyway, but even if I did, it would have been difficult staying asleep with near constant barrage of (really loud) announcements (in Chinese and English) during the first 2.5 hours... "We will be arriving at Wuxi in 5 minutes", "We are arriving at Wuxi Stn now", "welcome aboard our train to South of Beijing Station. The next stop will be Nanjing West", etc, etc.

Eh, for me meeting locals usually means meeting a younger college age student to strike up a nice conversation. With no mandarin, you might find a student that wants to practice English. Most like these types aren't the scam type and offer a good opportunity to figure stuff about China.

Makes time go faster if you ask me, but then again with the 4/2 person berth's you can spend hours watching Chinese Kung fu movies too.

Never did get the logic behind putting chairs in a hallway. Must be a respite from cabin mates. Goes along with that harmony theory.

Though not available on most CDG services, the very best class-of-service for meeting the locals and practicing Mandarin (or be an impromptu English teacher) is HARD SLEEPER. On longer distances, hard seat has too many farmers (not to mention an agonizing, sleepless experience) which makes your focus Survival Without Going Insane rather than socializing. Soft sleeper is too enclosed and isolating. I've whiled away many a pre-sleep and post-sleep hour chatting, playing games, etc with ordinary Chinese in hard sleeper. When traveling solo on ZTK/number services, my first choice if I can get it, is always hard sleeper. I do not like to risk being shut in with 2-3 men in soft sleeper, and the lack of air circulation in softs make it uncomfortable for me to get much sleep.

However, I have heard anecdotes for years that for women traveling solo in Deluxe 2-person class, they will try to assign you a cabin to be occupied by another woman when possible...or the carriage staff will reassign you in real-time to be in a woman-share situation or by yourself in one cabin (if a vacancy is available and no woman-shares are possible). I have not soloed on this class of service so cannot vouch for on a first-hand basis.

No "teahouses" on the train!

It's really bad that MoR replaced Z trains between SH and BJ by D/G trains which are lot more expensive. Personally I like Z trains.

BTW, Nanjing West is almost abandoned. No C/D/G trains go there. :p