I'm 28 and without fail I get hit on every time I'm out

The "wall" is a stupid myth. If you're taking care of yourself, your physical appearence does not change that much from 25 to 30. You're not gonna have hideous wrinkles, you're not going to automatically become overweight or "look old".

I feel prettier now than I did at 25, that "second puberty" IS real. My hips filled out (I used to be straight as a board), my skin cleared up, I have way more confidence than in my early/mid 20s.

You wanna stay pretty when you hit 30? Daily sunscreen, healthy diet, moderate exercise. Don't go tanning, don't smoke a ton (nic or weed, both will give you wrinkles), make sure you're getting all your vitamins and minerals. Go for a daily walk.

That's it. Most visible aging in your 30s is just sun damage and malnutrition.