I used to get bundled up with tee shirt, 2 fleece sweatshirts, and heavy leather jacket. Ski pants, bacalava, and heavy gloves. I was pretty much ready for a moon landing. This year, I finally broke down and bought a heated jacket and gloves, and a full face helmet. Now, I wear a thin tee shirt, heated jacket and gloves, and whatever leather jacket over top, along with the full face helmet. That keeps my upper half far more than toasty by setting the heat to low. For the bottom half, my legs were never a huge problem, but it's nice not to have them cold either. I bought some fleece lined jeans. I don't have to worry about pulling something on over my pants, I have all my pockets, I still look like everyday, since noone else knows they are fleece lined, and the fleece just plain feels pretty darn good. I bought several packs of Toasty Toes from the hunting section of Walmart. Before I put my boots on, I just stick one of the patches on each sock and I'm good for the day. I can't stand cold toes, and these things don't warm up your toes...they just keep them around normal body temperature. So don't expect your toes to fell warm when you use them, but also don't expect your toes to feel cold either.
I went with the heated jacket instead of the vest. If you have the jacket, then you have plugs at the end of the sleeves to plug directly into your gloves and you don't have to run wires through your sleeves to operate gloves. That, and the fact that I want my arms warm too...not just the rest of me. When I get on the bike, I only have to plug in one wire. The wire from my jacket drops down from the left front, so I have the cable coming out from under the front left of my seat (which when not in use, can be quickly tucked up under the seat and out of sight), so I quickly plug it in and I'm ready to go. I have the heat controller strapped to my left upper leg, so I can readily change settings. Because I have the cable well secured under the seat so only so much cable will pull out, I don't even have to remember to unplug it when I get off the bike. When I step off the bike, the connection automatically pulls apart. I can now move freely and certainly no longer qualify for that moon landing.
Unfortunately, the roads have been very messy here in PA, or I wouldn't be deterred by temps below zero. I've been out in temps down as low as 10 to 15 degrees now and I can honestly say that I haven't even come close to experiencing a chill. I suppose that there could come a time when I might actually want to switch on the heated grips and heated seat, but the few times I have, I've ended up turning those off.
I saw some heated insoles for boots at the bike show this weekend, that plug into heated pants, but I think they would make my boots too tight and I guess I've gotten along without the need for those. As someone else mentioned, a windshield is your first step though. There was a time when I had never ridden with a windshield and never saw the need. I don't think I could ride without one now. Okay, now I'm done rambling.