There are a number of things that drive trust levels. For the most part it is not strictly number of posts like on the old system.
If @cawebmaster wanted to, they could implement custom badges using the badge trigger system to emulate the old title system based on post counts and length of time on the forums. Those badges could then be used on the title card so people could get back their Veteran or Elder titles. The other things like Pray Warrior or Greeter could be implemented using the groups function and then even tie “Avatar Flair” images to people’s avatar (flair are little graphic overlays that show up on the “corner” of the Circle that represent your user in posts).
Back to trust levels.
There are 5 levels
Lvl 0 - New
Lvl 1 - Basic (earned after reading a specific number of topics, posts over a set amount of time - I think all migrated users start here)
Lvl 2 - Member (where most will likely land - requires a certain numbers of likes given and received, number of days visited, replying to different threads, et cetera)
Lvl 3 - Regular (visit a certain percentage of days and enter a certain percentage of threads over a time period, more likes given and received to multiple users)
Lvl 4 - Leader (this is manually granted only as far as I know)
Each level has it’s own privileges around posts, # of daily likes, flagging threads, splitting topics, et cetera. You can read more about trust levels here: