I fired up Suigi's quickstart and made a number of changes to have a tweaked version of the Quickstart - feel free to download and play:
1. Added two Indie leagues for Japan - create some job opportunities for those undrafted players and those out of the league, once a while, one of them turn into something special.
2. Added short season A, simple NCAA and HS feeder systems for MLB - more talent for MLB, more talent for JPBO (those who cannot cut it at MLB will come to Japan).
3. Added AAA, A, and Rookie ball for JPBO - you gotta have an environment for those 18 years old rookies play and develop against their peers, and not get destroyed by career minor leaguers. Feel free to remove AAA or any level if you see fit since I did not generate fictional players to fit the rosters - ghost players for incomplete rosters is enabled so you dont have to run with a full roster at every level.
4. Added AA ball for KBO - same concept as JPBO, you have to separate those who are u20, and those who are over 20 to help with development.
5. Deleted duplicate staff - man this cost me 2 hours just deleting over 1,000 duplicate coaches and staff members.
6. Additional tweaks for league settings - minor settings.
7. Renamed Fukuoka Rings to be Vipers (purple and snakes perfectly describe the evil empire feel of Fukuoka), and Sendai Woodpeckers to be Hawks (well Hawks and Eagles are different, right?).
8. And more small tweaks I cannot remember.
Bonus tip - the talent pool (especially Japanese players) at the start of the save will be very small so I recommend you use commissioner mode to fill the minor leagues with fictional players for JPBO - teams will have a better kickstart with prospects and depths that way.
Update: Tweak 2
1. Updated the minor league systems, with team names, uniforms and logos
2. Updated ballpark factors for JPBO teams based on OOTP23 numbers
3. Small changes to league settings based on OOTP23 numbers
https://mega.nz/file/HctVTQjK#4P84ES...lzlxX9ePpxPNlw