The top tube length (feeling stretched?) is a better way to 'fit' the bike than the size or stand-over. It sounds like the Bianchi Vigorelli you tested may be too big. It is also possible that the handlebar on the Bianchi may have more forward reach, drop, or be too wide, giving you that stretched out feeling. I used to ride a lovely Scapin with Colombus SLX tubing back in the 80s~90s. I loved that bike but it was too big- no stand-over issue but the TT was too long. I went the short stem, short reach bar route and that made the bike twitchy. I finally gave it to my taller niece (I'm 5'1.5") and bought a 44cm bike.
Bike Chick is right about the compact crank vs. the full size crankset. You will notice all your climbing gears are gone with the full size crank if you relied on the small ring of a triple to crest hills. Heck, you will probably notice that a good many gears are rather tall and probably not very useful. And now that SRAM makes a 11~32 ten speed cassette, you could easily get as low a gear with a compact crank as you have now on the triple, with less weight and a better chainline and less shifting (and less chance of dropping a chain) than a triple.
You didn't mention your height/inseam (or maybe I missed that somewhere?) As you have a bike now that sounds like it is a bit too big since you had to go to a short stem, measure the top tube length, and the length including the stem. (Measure stem to the center of the bar) You could then compare the sizes offered from Bianchi, Kona and other manufacturers at their websites. Match the overall length (stem+tt), then look at the TT length. That would be closer to your size than what you have now. As I'm so short, I ended up with a WSD bike, and for once I actually went to a 5mm longer stem than stock to to tweak the fit. The bike handles like it was custom made for me (it fits it fits!). While I miss the feel of steel of my old Scapin (made in Italy too...) I love that my current ride fits and that makes all the difference.
Tzvia- rollin' slow...
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