I actually think we are well positioned to sign Acuna again. He is currently making $17mm a year until 2028! That is 5 more seasons. That is a really long time for Acuna to only be making $17mm. Its ironic but the reason will be able to extend him is because of how good the current contract is.
Our leverage is we could do nothing and ensure the next 5-years he makes $17mm - and by definition we are the only team that can increase that - and we clearly view him as worth way more than that.
Just using dummy numbers, lets say this offseason we offered to add another 5-year extension to his deal for $35mm per year to the current contract. That would be his age 30-35 seasons. In that same scenario we could also agree to increase the next 5-years to $35mm per year. That would really be the equivalent of telling him that by agreeing to a 5-year extension at $35mm, you really are playing out your current contract, and then getting an extension for 5-years at $52mm per year ($35mm + the $17mm increase over the next 5-years). In that same example, we are basically saying on top of all of that, will give you half of the money from the second 5-year contract over the first 5-year contract.
In that same example if he declined the deal and played out his contract, then to be made full as a free agent, he would have to earn $52mm per year over the ensuing 5-years period.
It obviously is not quite that simple and this is a generic example. I'm sure he will also be focused on delivering something closer to a 10-year contract extension at age 30, but the point is, we have really good levers to solve for a "max free agent contract level" just by restructuring the current deal, in exchange for somewhat reasonable levels on the extended years.