How To Make a Campaign more fun [closed]

I’m building a campaign for my players and I want it to be the most fun and enjoyable campaign possible. Just some background info. Me and my party have been playing D&D for about a year and a half now. The campaign works off checkpoints for leveling so the players are guaranteed to hit every level 1-20 before it’s over. This is also a sequel campaign in the sense that it takes place in the same world as a past one but thousands of years later. I saw on Critical Role that they ran PVP one-shots in like dream world but it incorporated their same characters and with my PVP loving party that is a great idea that I want to implement. I’m asking you guys what other cool ideas can I throw in ( one-shots or multi sessions) that could just make this campaign more fun