KIX arrival / departure

Hi, I'm starting to plan a 2 week trip to Japan. We fly in and out of KIX (from Seoul) and were curious about the timing of our flights. We will arrive Kansai in the evening around 21:05. Considering customs/immigration, will we have trouble getting to Osaka or Kyoto? I read the last Haruka Express is at 22:15. I'm just worried that since we don't know the airport, that we will miss it.

For our return to Seoul, our flight is at 10:15. How long is the trip to Kansai from Osaka / Kyoto and would it really matter which city we spend our last night. Thanks

We will arrive Kansai in the evening around 21:05.
Considering customs/immigration, will we have trouble getting to Osaka or Kyoto?

For Kyoto City, you may miss the last connection of the day.

Unless the immigration procedure extraordinarily takes long time,
you can get to Osaka City, I think.

According to the current timetables,
the last JR direct train for Osaka (Umeda area)
is Airport Rapid
which departs at 23:09 and arrives to Osaka at 00:14,
and the last Nankai direct train for Namba
is Airport Express
which departs at 23:55 and arrives to Namba at 00:39.

Unlike JR Haruka and Nankai Rapi:t,
these slower trains are not designed specifically for airway users.

The last JR Haruka departs at 22:16.
The last Nankai Rapi:t departs either at 22:55 or at 23:00.

When you go by JR for Osaka City,
note that Osaka Station is not the last stop.

("Osaka" and "Kyoto" each may refer to the prefecture.)

- Japan Guide: How to travel between KIX and Osaka City
https://www.japan-guide.com/e/e4006.html?aFROM=2033_2157

- Japan Guide: How to travel between KIX and Kyoto City
https://www.japan-guide.com/e/e2363.html?aFROM=2033_2158

Hi
For the arrival ques.
Another option is staying when arriving late in an hotel in KIX airport . I used this option twice . Only next morning we made our way to Kyoto or Osaka

Arrival - true you may miss the last Haruka, but if you are ok to do things on the fly and don't have enormous amounts of luggage, you may still be able to get to Osaka and from there to Kyoto. Trains run Osaka to Kyoto until quite late, for example Hankyu from Umeda until close to midnight. But be sure to check which station exactly as you may need to transfer in Osaka. It could be daunting if you are not familiar with stations / ticket machines though.

Return - there are minibus services running from Kyoto to KIX on demand that you can book to collect you at a specific address. I used to take these when catching morning flights. They weren't very expensive. Your hotel may be able to book them for you. Of course it means an early rise. I don't have details sorry, it was too long ago. This may also be an option from KIX on arrival, by the way - worth checking.