Increasing the variety of beverages offered and the days and hours they are available is always a good idea.
Customers appreciate a full service location that is unrestricted compared to the competition as far as times or days of the week. The costs of increasing sales through a local option easily pays for itself within the first year and your permit will be with you for life.
Beyond that, liquor permits have value on their own. Typically three to ten times the fees to maintain it for a year. They are in great demand in counties with larger populations as the quotas are full and the applications outnumber the permits available by the hundreds. They can be sold and transferred to business who are unable to secure permits due to these limits.