It sounds to me that you are pretty much on the right track with your clothing. A few suggestions.

Keep the three layer top system you are using but substitute polypro or wool open weave long sleeve SKI long john instead of Underarmor. Much warmer, breaths better and less expensive. Swap out the mid layer cycling jersey for a mid weight cheap breathable fleece jacket or merino wool sweater. Old navy sells those cheap fleece pullovers for 20 bucks or so. You can buy a size smaller than usual to get a kind of form fitting insulation layer which works well under and outer layer. This is much warmer than a cycling jersey and pulls sweat out away from the body to outer layer where it can more easily dry out. For outer layer you need a Goretex cycling jacket. Nothing works better for colder temperatures. Goretex blocks cold wind better but still retains some breathability. Bomber jacket is probably too breathable and probably insulation is absorbing too much sweat and acting as an air conditioner. It seems to work better if the outer jacket is un-insulated. Use thicker mid layer if not warm enough.

If you don't have funds for Goretex cycling jacket (they can be expensive). You can use a Columbia fleece lined nylon supplex jacket in a pinch. In this case the jacket lining is the mid layer so just use the jacket over the long john top. These are just those 40-50 dollar jackets with the zip up front and collar. Looser fitting than bike wear but will trap a lot of warm air around the mid section.

Problem with light wind breakers for outer layer is that they are usually too breathable for below freezing temperatures, but can work for riders that run hot and need extra breathability.

Alternate is to use heavier cheap mid and outer layer fleece that is pretty breathable. But you have to use thicker layers to compensate for the lack of wind resistance. And it doesn't work as well in windy conditions. ALso, you will be wetter, but can stay warm if outer jacket is hard surface tight knight type of fleece. Like is popular nowdays for light mountaineering jacket.

Also, you can wear a standard pair of cycling shorts under the bibs to keep the thighs and pelvis warmer. THis will help keep your whole body warmer. And I would suggest this for 25 F temps unless your legs run really hot when riding.

Some guys might get cold with wind breaker pants on the legs over tights because the legs will be too warm and the pants trap excess moisture which can travel through the material up the torso and into the upper layers. I personally think it's better to keep the legs as breathable as possible to keep them dry. I've found that in really cold conditions it's better to layer breathable cycling tights and shorts to get the needed insulation factor. This keeps the legs more breathable than hard materials can. In the end it has always kept me warmer to keep the legs more breathable. The reason this insulation/breathability balance is so crucial is because a little too much trapped moisture in the system will almost always chill you. And you'd be surprised how much capilary action can transport excess moisture around into other garments and make them less functional. I think that's what the main problem is with your present system. It seems your trapping too much moisture because you should have enough insulation on for the temperature.

I would try an inexpensive pair of tights over your bib tights which I assume have a chamois in them and ditch the wind pants. If that still not warm enough on the legs add a pair of cycling shorts underneath.