It looks like Romania and Bulgaria are closer to implementing the Schengen Agreement, as soon as March of 2024.
They have ironed out some differences with Austria, the main objector to the move.
I assume the partial agreement will retain land border checks, but from the perspective of your 90/180 days, days in country will count toward your 90 regardless of how you arrived.
Of course, no final decision yet, but be aware for planning. A number of people were messed up with planning when Croatia implemented Schengen.