How much of your wardrobe are you hoping to wear everyday, 50%, 70%, 80%? One thing I've learned from many closet purges that never stuck over the years was, my needs change and that can swing how much of a certain capsule I am using at a given time. If I purge too fast, or too much of a capsule prematurely I end up repurchasing.
Within your FL wardrobe, it sounds like you are currently using 50% (is that correct?) which is pretty good! After all most people say we only use 20% of our wardrobes. New wheels may or may not influence your wardrobe. For me, car transportation or not influences my shoes the most. My NYC days, it's flat walking shoes only but my drive to work days, a heel or sitting shoe is ok to use. But the rest of my outfits are the same most days.
I think you've identified a mini capsule in your FL wardrobe, which has been your bike/errand running around capsule. This is great news, because now you know your 'set point' for this capsule, which is what the DH challenge is all about anyway. I wouldn't get rid of other items too fast, have you used more dressy items on past FL trips and this one is just more casual? Or has your FL lifestyle truly changed, in which case, you can purge dressier items. The one thing you can definitely do now, is not purchase anymore of the dressier items you are not sporting.
Also, weather plays a big role. Has it been overly hot and humid in FL, which has influenced your outfits? Last year, we had the coldest winter in the northeast that I can remember and I have never worn my thermals so much before. But before I go stocking up I want to make sure this winter will be another cold one.