Hang some smaller scale vintage sepia tone photos (will help pull in your brown countertop). Use black frames.

That's a large vanity. Do you really need more storage over the toilet?

I like the idea of hanging photos or artwork here instead of a visually heavy cabinet.

I love your shower curtain and wall color, by the way!

I was also thinking one of these wire hanging units might work well:

http://www.vivaterra.com/modular-wire-shelving.html

I think art would really take this room to the next level -- the right picture would bring color and/or help tie together the elements you have.

We agree with the above comments that the right artwork will look great in that space. Of course I have to include a link to one of the farm scene plaques we sell on our site: https://www.dutchcrafters.com/American-Made-Berks-Co-Sunrise-Plaque/p/59859. 

A barn star may also be a good option since you mentioned industrial farmhouse: https://www.dutchcrafters.com/Barn-Stars/cat/407

Live edge shelves held up by iron brackets, or industrial shelves like these from our sister-site EcoFriendlyDigs.com http://www.ecofriendlydigs.com/Shelves/cat/325 will also look great in the space, and you can decorate them with pictures, plants, etc.

Nothing…I like the bathroom. My only suggestion would be a white frame on the mirror to correlate with that great window.

Agree with the white-framed mirror. If you don't need the storage, I'd keep it very simple. Maybe a small plant on the back of the toilet, and a little, intimate piece of art that could be on the wall above the toilet or to the side just above the wainscoting, so it can be viewed when... well, when you have a moment, shall we say.

If you need a place for towels for guests, you could get a shelf with a towel bar below. And if you need more shelves, I like simple open shelves.

Here's a couple of photos I found attractive:

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Some artwork would look nice behind the toilet, and like others said the mirror framed in white might be nice.

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Some plants maybe? Either hanging from the ceiling or on a shelve?

I would be looking to coordinate that entire wall and perhaps the 1st picture below would suit the direction you want to head - maybe too rustic? With your wainscoting, not sure how industrial you should head. You could add some new hardware to the cabinet to match your faucet and other metals.

I really like the round mirrors I've been seeing lately. Nice and different. If you get one that's hung from rope or leather, I think that would tie in with the effect you're looking for.

If you want to save a little money though, I think you could just paint the frame of your current mirror the same color as your trim. Maybe lightly sand a few spots to make it a little more rustic, and it would probably feel like a brand new piece. Chalk paint with a wax finish would also work well.

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Plants with grey blue walls will look fantastic. They add life and vitality to any space. I think they will make your space fell very fresh—look how many sample photos have been posted with plants or fresh flowers in them.

Regarding dusty house plants... very easy to stick them in a gentle shower for a few minutes every so often. They get clean and watered at the same time and you can let them sit there a few minutes to drain and dry off. Unless it's an African violet or something that prefers not to get it's leaves wet, plants love it! That's also a great way to help prevent or get rid of spider mites that is a common indoor plant problem.

That is such a big countertop that a small mirror will look unbalanced. You could always get that mirror reframed in something farmhouse/rustic. Hopefully they didn't glue it on or it's gonna rip the drywall. It's just something to consider. One small job can turn into a big job really fast.

What did you end up putting above your toilet area?