You have Aaron Rodgers.

That makes the choice easy. You keep Bulaga and ensure having a deep, talented OL to protect him.

While Cobb is a fabulous talent, a QB like Rodgers can make average talents look pretty damn good if he has an OL to protect him.

That said...with $30M+ available to spend if Thompson does the right thing and takes an axe to the deadwood on the roster...there is no need to have to make the choice. You keep both.