Painting both the doors and storm doors a lively color (without seeing the whole house it's hard to pick one). I'd go with a large rectangular rug.

If it were me, I would buy an outdoor carpet that would fill that entire space. Something natural with some color (like red, orange or green) in the pattern. Then get some new house numbers and brick clips for hanging outdoor art, wreaths or whatever. You could get some larger potted plants or flowers for next to the door. And if you are able, replace the light fixture. It also seems like you have space to the right of the door where you could create a small sitting area? Or you could put a bench against the brick wall. The are lots of possibilities!

I like the idea of the bench with a colorful cushion. Or you could do chairs. Two tall planters and an outside area rug. Once you find a rug or cushions you like you can pick a paint color for the doors.

Perhaps a low planter with a beautiful metal trellis:

A rug that is wider or narrower than door but not same width. I would leave some border of porch surface tho. Two tall plants or conical shaped trees at posts before step on porch. Maybe shade near but not exact as brick mortar or a cream, ivory or gray. A wreath on door. Sitting area or small garden or koi pond to right or a water feature.