One a large feast day there isn't anywhere to sit.
They remove the pews (or chairs if your chapel is that bad off)? Get there early enough to get a front row seat.
Or keep your eyes glued to your missal, and the eyes of your soul glued to God. Practice custody of your eyes. There are enough ads in the world that you can practice the habit by never looking at ads (even if they are clean).
It's great that new people come, but there needs to be a plan in place to make sure they are made aware of how to dress modestly, even having some designated kind people to offer them something to cover up with.
Keeping the church cold, which may require an AC system upgrade, should help regulars to dress warm.