You should make this plugin support PlayTime Rewards: https://umod.org/plugins/play-time-rewards

Yes Please

Why ? , This plugin allows you to give ranks according to the amount of time on the server, those ranks (created groups) are used to gain permissions to players , for instance so that they can claim kits , extra Nteleportation spawns, amount of /sethomes, extra backpack slots and anything else that has a permission.
The other plugin has a different set of rewards.

And where do you get your playing time for the players?

As it says in the documentation
works with

• Connection DB
• Playtime Tracker
  
  I use playtime tracker.

Playtimetracker but it's not that great. and the other one is not up to date and it doesn't say use.

I have been using it for PlayerRankings for about 5 years and have no problems with it. I did use ConnectDB for 2 years but found that if it updated at the same time as PlayerRankings i lost players time. I dont have that problem with PlaytimeTracker.
What do you use ??

Started with PlayerRankings and PlaytimeTracker in combination with BetterChat and it´s working perfect since years now. Only my opinion. The only thing i miss is a start delay for the afk tracker in PlaytimeTracker.