YVR overnight suggestions
 

I have an upcoming YYZ-YVR-TPE on AC, with an overnight at YVR (Holiday Inn YVR) between 9pm and 11am (flight times) on a Saturday.

I will have checked bags and as far as I know I have to take with me to the hotel and recheck again next day. Hotel has shuttle service.

Question: Given the late arrival and early departure (have to be at airport by 9am) what is there to do and/or eat? I would like to go downtown but the train may not run that late or early enough, plus I need to store bags at hotel first.

HI Express or the one at Shell/Cambie? Both of them are in the dead-ish 'burbs/light industrial/commercial that time of night. The HI Express is closer to the RAV line than the HI.

There's a 24h Chinese restaurant at Lansdowne mall but it's a bit of a hike on not-nice-to-walk roads from either. The HI seems to be close to a casual local chain restaurant (Fog 'n Suds) which I haven't been to one in over 30 years.

Check Translink for schedules.

It's the holiday inn vancouver airport, doesn't look like it's walking distance from any train station.

I'm debating whether to rent a car for the night so I can drive somewhere, but not sure what's going to be around past 11pm or open before 7am.

I can also do a same day standby/change to earlier flight for $100 and arrive by morning, but not sure if it's worth the cost just to get more time.

The Fogg n Suds (looks like it's the only one left) is attached to the HI. Food service ends (or last seating) at 1030p though. On the same block is a Mickey D's.

There's a mini mall a block (1/2 km) east that has some eateries. Couple of the asian eateries seem to be open until midnight. Passed by but can't say I've ever eaten anywhere in this area..

Not that I'm advocating gambling, but River Rock Casino may have dining options open later than a stand-alone restaurant. It's been a while since I've visited there, but it's relatively close to your hotel that the cab ride shouldn't be terribly expensive. (I'm guessing $10-15 each way (I find Richmond traffic is terrible), so should be cheaper than renting a car, plus parking fees at hotel.)
Since you're headed to TPE where you can get your fill of Taiwanese/Chinese cuisine, the casino will at least offer some other options (burgers / pizza, etc). I'm not sure if the "fine dining" options will still be open though.

Thanks for the suggestion. I was somewhat looking for street eats or interesting places to explore in Vancouver but I think they're not going to be open during those time plus likely not idea at this weather.

OK I think I can arrive early around noon, and explore the city a bit. Is the weather ok for walking a few hours say on the street and in stanley park? Also, is it easier to just rent a car or am I better off taking the skytrain? The car is about 20-25 plus gas and hotel parking of 10, but I would have to find parking I think around places I visit.

I usually just take the Canada Line to downtown and walk around on my day excursions to Vancouver.

Weather is usually ok for a Stanley Park walk.

Yep, as YVR Cockroach similarly mentioned, the area around the HI by Cambie and Shell is definitely a deadspot for a tourist IMO. I used to play softball at a nearby park.

The weather is really hit or miss in Nov and Dec. It can be sunny, clear and chilly or rainy, and miserable.
Arriving at noon, skytrain is likely an option to get downtown and back (although not too late) but you'd likely need/want to bus it to and from the Aberdeen skytrain station from the hotel. It's not a horrible walk but it's not very interesting until you get about a block or two from the station where there's more retail activity.
The problem with renting a car, especially going to downtown is that you'll likely have to pay for parking, even in Stanley Park. There are a few free spots though on Saturday like eastbound along Georgia btw Nicola and Thurlow. If you end up just looking for a parkade, the orange EasyPark lots are good options but their rates do vary depending on the area/lot you choose and there are might be better options pending where you want to be and how much walking you want to do. IF the weather is nice, after you park the car, walking to various areas in the downtown core (including Stanley Park) is fairly reasonable. Comparatively, you're likely looking at a $35-40 ride each way using a taxi.

Normally a lot of the food carts close up shop for the winter but I'm seeing a lot staying open and/or attend special events. You're not going to see as many in downtown on a Saturday but there will still be a few along Granville street and on Robson by the art gallery. If you have a car, you might be able to make the Farmers Market at Nat Bailey stadium which is open to about 2pm and has a few carts. Chinatown is a shadow of its former self as Chinese retail as decentralized. However, there's a lot of interesting food options (not necessarily Chinese) that have opened up in Chinatown likely due to cheaper rent but still being close to downtown.

Yep.

IIRC, the one by domestic luggage closes at 11pm daily, and the one near International/Transborder arrivals is 24/7 (?).