Sign Blake Snell
Blake Snell is arguably the best pitcher still on the free-agent market. He's been a less realistic target for the Red Sox than Montgomery all offseason because he's asking for an astronomical contract, both in length and in price.
Snell is a two-time Cy Young Award winner and his presence would definitely improve the Red Sox roster (which is not saying much these days.) His 2023 season was his second Cy Young year and he led MLB with the lowest ERA for a qualified starting pitcher at 2.25. Snell pitched 180 innings and logged a staggering 234 strikeouts.
Snell lets up a lot of walks, though, which could end up being a curse for the Red Sox's shoddy defense — one of the worst defensive teams in the league can't stand to put more people on base.
But a starter that gives up a lot of free passes is better than four relievers and Bello in the starting rotation. Snell would give the Red Sox strikeouts and mileage that they would be hard-pressed to find from anyone else available. He would be expensive, but with the recent news that he and his agent Scott Boras would accept a deal like the one Cody Bellinger did from the Cubs, Boston could, and should, swing it.