22L is 5.8 US Gal
Yes, your LS plan will overpopulate the tank.
Perhaps you wanna reconsider the following:
3) Royal Gramma - can be quite aggresive in a small tank
4) Mandarin - unless your tank is matured with lots of food hidden within ur LR, not all Mandarin can be trained to take feedings
You can have the following but make sure you buy very small specimens:
1)
2)
5)
Items 6) and 7) are suitable for new tank and can spread pretty easily if the condition is right.
Oh... your pH of 8.6 is a bit on the high side.