The reason people played Invadedlands in 2018 and 2019 was because of Skeppy. They came on for a chance to see their favorite YouTuber and have a chance to interact with them. Skeppy's neglect of Invadedlands is what has caused the server's population to decrease with time.
I understand that the rationale behind this change is to attract a new crowd, but you're just going to end up using a hammer to embed a screw in the wall. Your solution does not address the problem that the server is facing... In fact, I think it only makes it worse.
You have to assess the demographic of your players. Most of the people who play the game today and continue to keep it thriving are players who compete at a very high level of 1.8 pvp. These people are the kinds that play on practice servers and place highly on leaderboards.
1.9+ pvp is radically different from 1.8, you may as well consider them two entirely different games altogether. By changing the gameplay style, you are alienating those who have dedicated time to improve their skills at 1.8 to the point that they are good enough to compete at leaderboard levels. As someone who has played on Invaded for nearly five years, I can tell you that as time has passed and more and more Skeppy fans have quit, the only people keeping the server's population afloat are the pvp sweats of 1.8.
This change, while aimed to draw new players to the server, will alienate its existing playerbase.
Is this really what you want to do?
If you want to revive the server, Skeppy needs to play on it to draw his fanbase back to repopulate it.