I believe PSO2 would thrive more for the people if there was a marriage system added to the game. it would bring people together, give people something to talk about, and possibly bring people back to PSO. There can be special things that can be given to people from special items to new fashion clothes. Marriage has always been a big thing to people and just about every game has one and they all have done pretty successfully in the sense. Of course, the only drawback that could ever come to a person's mind is you could be sitting in the lobby and a random person comes up to you and bugs you to marry then but that is why we have a block system so a person does not really have to deal with stuff like that for very long.
How the system could work is there can be a big event that can have a set date so people know when to attend, special fashion outfits can be given out to the bride and groom along with a special ring. People that attend the wedding can get special items also that do special things that can give Power boosts, Experience boosts, or Rare Drop boosts so; it would give the person a really good reason to attend and the person that is getting married would really feel like it is there day.
There can be tiers of weddings that cost Star Gems to activate and the higher the Tier the higher the gifts.
Tier 1 can be just a simple wedding with the lowest set gifts and rewards. it could cost 200 SG so even people that are just starting out can afford it and it can be really fun for the new person just starting out also it would get the person thinking "wow maybe ill stick around this game for a bit longer than I thought."
Tier 2 can cost 500 SG and would be the middle event of the wedding. It would have more to offer from the ceremony to the gifts along with better stuff for the people that attend.
Tier 3 can be the grandest of ceremonies of the wedding. It could cost 800 SG and give the best possible rewards and gifts along with a special fashion outfit and the highest rarity ring.
There can be a special Tribooster that can apply to the happy couple for as long as they are in a party together. If a couple were to first join the game and would be looking to get married ASAP just so they can get that little extra boost they can do the Tier 1 wedding and then later down the road, once they saved up the SG, they can do the Grand wedding and get the better things that come with it. If divorces were to ever happen there can be a timer set on the two people where they cannot get married for 6 days and there can be a 24-hour cancel timer of set divorce so if the couple changes there mind they can stay married instead of going through the whole waiting process.
This is just a little thought I had and I do think this would help the game really thrive. It would give people something to look forward to in the game and maybe add much more excitement to it.