Yo could continue the tile on the entry floor up the wall. You could also make a faux sidelight famed out with mirrors. One other option is to use the material in the entry ceiling. The last idea I have it to stucco the area.

Would you step back & take a picture of more of this side of house & maybe include the new front door if it's close to this inset where the entry door was? Not understanding what the new slate herringbone tile was installed for if this isn't your entry anymore.

This is what it looked like before; the sidelight is gone, and the door is moving over where to it used to be, leaving a blank space that cannot be a window.

ok I get it now. Front door moved to left (looking at it) in the same space. Maybe as houssaon suggested, use the entry ceiling material. Im looking at the white plank looking pieces above the soffit. That would be brighter than using the slate. Instead of a white door maybe a color? Pale gray tone to play off slate? I'm looking at your house numbers on the brick above the entry - very hard to see in the picture - how about bigger numbers in dark metal on the white paneled inset next to door? Maybe place a small pot with tall evergreen in front of it or find a tall piece of something interesting - pottery etc to add. Question - is your new door going to be standard sized? Perspective skewed in pic & looks narrow.

If you still have the glass that was there, you could reinstall it with a reflective foil behind it.

Really interesting ideas, thank you everyone. It might look skewed because there's actually an angle on that wall, so the left side of the porch is shorter than the right. It is a standard size door (36") going in there. I like the idea of tying in the ceiling, that's something I hadn't thought of. @NancyD definitely not too late to add a light there, and having the house numbers vertically could look cool.

Can you post a photo of the whole front of the house. This area should tie in with the whole house to make it look cohesive and not just the front door area and so we need to see it all. And what does the new door look like? What is going to be on the right side of the door where there are the horizontal boards? Is that just a continuation of the area to the right of it?

Can do... whole front and door here. Those shutters by the windows are getting painted white as well, and the roof has since been replaced with light gray shingles.