Unfortunately I didn't get any replies yet, so I did a search online and found this really useful guide about South Korea tourism statistics for 2023
https://gowithguide.com/blog/south-korea-tourism-statistics-2023-all-you-need-to-know-5254
It has a lot of great info on transportation options (looks like public transit is really convenient), top attractions to visit beyond just Seoul, and even trends for this year. The guide also includes some basic Korean phrases at the end which should be helpful.
Seems like their public transportation system will make it easy to get around the major cities from the sounds of it. And it gives some cool festival dates to check out if I happen to visit during any of them. Really helpful overview to get me started in the planning process.