The sconce on the left seems to be lower than the 2 others (not lined-up).

Is this an illusion or is it another hitch in your DIY?

Sconce is the same height ... just count the tiles and you can see that it is the same

The mirror size you show does not fit the space and highlights that everything is off.

Just do 2 larger oval mirrors that fill the space between sconces. Just ignore part of the asymmetry.

I did count the tiles and the sconce in the middle is higher.

I agree with JAN MOYER'S suggestion to tear down the tiles and install a large mirror and make sure this time the outlets for sconces are all well aligned.

I'm sorta with @JAN MOYER on this one. I like the tile, but at the mirror level, have a custom rectangular mirror the entire width with the sconces mounted thru the mirror. The other option would be @chispa's suggestion - two much larger oval mirrors that fill the wall space between the lamps. It's just preference. I think both options would look equally nice.

She hasn't enough room for a framed mirror. Sorry no.

And no round or oval will prevent an off kilter look to the faucets:

You gotta take down the middle sconce and replace it with two placed close to the mirrors, so that each unit over each sink is symmetrical and looks right (with two sconces properly placed to light the viewer). You can probably fill the hole for the one that was there...

I would remove all 3 sconcesand return or find them another home. Choose the mirrors you like of appropriate size and center over each sink. Put lights over each mirror.

Thus

I don't see anything in this design that requires oval mirrors to complete a "look." There appears to be more than one mistake here, and the beveled plate mirror with re-jiggered sconces so that two properly flank each basin will take care of all of them and look fabulous!

The wall has too much going ON. Tile, sconces, ovals, space overkill in between the sinks. You don't even need the bevel on the full area mirror.

Do the whole back, align the sconce error, and be pleasantly SURPRISED.

It's not difficult to get caught up in a bit of design overthink, which is what happened here courtesy of internet images..........and the result becomes one of "UNDER think". The main question being does it work in my space?. All aspects. So? It didn't go as planned. It's a simple and extremely easy fix, drywall is cheap, so is mirror with a template.No more "kludge".....

Kludge is just the "I'll have a little of this, a little of that" and it just became too much meal lol

Jan’s suggestion has always been my favorite look.

If you can’t bear to sacrifice the existing tile work i would use larger mirrors centered on the wall and sconces.

IMO Jan has the answer or you just live with the booboo IMO no other choice . I guess it is your private space so the only one seeing it is you. I will tell you sometimes what seems to be a bad thing in design turns out to be a much better solution.

You might look into either adding a mirror like we used in our design included below or adding an extra sconce to make things more even. Please look to this design we have done for a client:

California Ranch Transformation · More Info

Maybe not what you envisioned, but practical.