I would live with it for a while to see if it grows on you. From a standing position, you won't be staring at the door fronts at the same angle as the pictures, and you won't be in there as much since it's the guest bathroom. I had some drawer fronts in my new kitchen that I didn't like. People on here told me they were fine, so I tried to live with them. After a few weeks, they just felt wrong and I had them replaced. Cost $1000 for the new fronts and labor to install. Now I love love love them! They were very "front and center" in my kitchen, where I was looking at them all the time. If it had been a more expensive fix I definitely could have lived with them, but for me it was worth $1000 to change them out. However there were other things that bothered me at first but grew on me. So I'd try to live with them, then consider replacing if you still don't like them and have the budget.

To get a modern feel with that vanity, i think you'll have to do the rest of the space pretty stark/minimalist -- maybe a silky medium gray paint and a very plain, maybe industrial feeling, mirror. Not sure anything else about the room can stay the way it is -- the vanity will really be the star, and all the art and color choices will need to support that. It looks like your flooring might need replacement anyway. I don't have the time to find a really perfect inspiration pic, but here are a few that might point in a direction... Dunno if I'm conveying what I have in mind, but anyway, modern + elegant is quite a nice mix!

I agree with Cpartist"s layout and like moving the closet over as suggested by D M so that bedroom 3 has easier access to the bathroom. Do you have room to have the toilet face the tub and add a linen cabinet next to the toilet? How wide is the tub toilet area?

For a more modern log home you would pick colors the same way you would in a regular home - bring all your pieces together and draw a color out of them...if you are really feeling the country then you may want to be in sage greens, pumpkin, fall reds and things like that. I do agree - no need to paint before cabinets go in - don't rush... find colors you are drawn to and paint poster boards and hang them up and look at them for a week or so... Good luck!