Don’t forget there are other kinds of benefits you could offer. For example, anything related to work life balance: 4 day work week, more generous PTO, reduced summer or winter hours. Get creative with it.
Also as you mention they have a really PTO generous plan. We also get several of the random bank holidays as holidays.
Another thing I like is they bought us a Linux Academy subscription, and we are given time during the day to us it. Which is nice as I like to learn new things, and this way I don't have to use my time to do it.
I actually chose this job over another that paid more because of little things like this.