A size 48 does not limit you strictly to WSD bikes. I ride a 47-49 as well and have a unisex frame.
You may fit better on a WSD, but if there are unisex bikes available for you to try as well (or order if the geometry is not different, which is still the case with some manufacturers especially in the small sizes) don't write them off.
I also wouldn't write a bike off based on the white handlebars or saddle. You'll probably end up wanting a different saddle anyway, and bar tape is cheap to swap out (even when I let the shop wrap them they only charge ~$25 for everything).
From what I've heard 105 is plenty good. I can't speak from experience because I jumped straight from SORA to Ultegra. I wouldn't let 105 turn you off and I wouldn't stretch your budget to uncomfortable levels just to get Ultegra.
All the companies you listed make great bikes, so it's just time to get out and ride as many as you can. I particularly liked the Scott Addict (equivalent to Contessa Race) and was surprisingly impressed with Specialized's Ruby. You'll be surprised at how different all of the frames/bikes feel though, so you have to decide for yourself what feel you like best. (For instance I'm one of the only people on the face of the planet that HATES the way the Trek Madones ride. Too smooth for me, but most everyone else raves about them).