Appreciate all the collective wisdom.
One reason Lecturer remains reluctant--desirable administrative career track at current institution (think: project coordinator, events planner, fundraising, etc.)
It sounds like you are choosing between two career paths as well as two institutions/job combinations for yourself and your spouse. If your reluctance to move is telling you that what you really want is an administrative track rather than a teaching/research track, that is a factor to take very seriously. The questions would then be: how secure/guaranteed is the admin track for you at your current place? Can you negotiate greater security in the admin track based on the TT offer elsewhere? What are the salary/advancement prospects if you take the admin track?