I'm glad I'm not the GM because I don't know how I would manage our RD heading into the off-season. There are two approaches in my opinion: long-term and short-term.
Short-term: Letting Bear go and moving forward with Larsson, Barrie, and Bouchard. This is a 'safer' path short-term but you're letting go of a kid who hasn't entered their prime and moving on with vets whose prime years are soon behind them.
Long-term: Opting to keep Bear and letting Barrie or Larsson walk. There will be growing pains in the short-term imo, but you're banking on Bear entering his prime which hopefully entails him being a solid top 4 D night-in and night-out.
Why I choose to keep Bear:
This is what I see as the long-term approach. Bear is 23 years old. He had a stellar rookie season (relative to expectations) where he stepped up in a big way when Larsson was injured for a month and gave us solid minutes. He's sitting at 106 NHL games played at the moment. He's yet to enter his prime. Meanwhile, Larsson was on a steady decline since that 2016/17 season and has only recently been playing pretty well. I don't think we should let recency bias cloud our judgment. I'd just hate to draft a kid outside of the first two rounds that actually made the NHL and let his prime years go to some other team. He's a smart two-way D and I believe in him.
My hope is to give Barrie an extension of no more than 3 years term. If Barrie wants more term or prices himself out I'm fine with letting him walk (which I think was the original expectation) and giving Larsson a short extension.