Congratulations on 24 years of marriage.
Why is it so wrong for your husband who is getting older and may need some extra chills and thrills in his life to get the blood pumping to want that for your anniversary? While you may be frightened to death of doing some things, figure out which one of those things you would be willing to do and go for it. You will be surprized just how much excitement that will add to you as a person. You will discover many things about yourself, your husband and your marriage.
It is refreshing for me to hear that your husband has no problem after 24 years of being married expressing his desires.
If you are not too thrill about spending and entire vacation on pursuing this endeavors, then I would recommend setting up a once a month outting of chills and thrills for your husband. Sometimes you come with him while other times you send him with one of his friends.
Don't be all weepy over past vacations which you enjoyed but he may have not. Men age differently than women. At least he isn't looking for that midlife crisis mobile and a twentysomething wifey replacement.
I say do your research and do your homework and get that man's adreneline pumping with some excitement.