In recent, I really stressed to play pve mission.
The mission itself is great, it gives us a heat to achieve certain goal.
However, the worst drawback of mission is ‘level selection’, and many players get salty with this matter.
For example, one veteran player with decent seed-chips and high pve bonus level matches with 3 newbie players who even struggle at level 5, he or she will find out this as a waste of time.
Same in the opposite way, a newbie player get forced to do a 20 level mission, where he or she can not afford it, and get an unnecessary repair cost.
So my suggestion?
Before match with other players, system asks players to which pool do you want to play: 1-10 level (easy mode), 10-20 level ( medium mode), 20-30(hard mode), 30~(maniac mode with warning plot), and then players will wait for sometimes to match up with other players in each pool.
For only for easy level pool, players can be matched with AI if waiting time takes too long, so newbie players can quickly level up his or her pve upgrade level.
Also, for hard and maniac mode, players can play with friends up to full party(meaning you can play pve mission with 3 friends).
This system also lead players in good ways.
In easy mode, players will practice the pattern of each pve mission, after that in medium mode, people will practice how to support other players in the mission.
In hard and maniac mode, players will practice how to be cool-headed in stressful mission and find out veteran’s know-how to quickly accomplish the mission.