Seems like we need a sticky on dressing for cold weather. The basics are really quite simple: dry skin, insulation, and wind proofing. The details are variable due to variations in humidity, temperature, and wind chill. Needs for a short commute are quite different than needs for a long pleasure ride in cold weather. On 5-minute commutes the battery needs all the power from the alternator it can get, so electrics are out. Also, most motorcycle gear is manufactured inside out, with the waterproof and windproof layer against the skin and gobs of insulation on the outside going to waste. I'm generally against liners in gear as they waste much of the potential for insulation and ventilation. Also, adding and removing liners changes the fit of the gear, and gear should fit properly to provide impact protection properly. I will tolerate a high-tech, thin liner such as Olympia uses, but the common vinyl liners that come with most gear are horrid winter or summer. Throw them away!
Add lightweight wicking undergarments under your street clothes to keep your skin dry. You'll be just as comfortable indoors as out with lightweight wicking undergarments. Heavyweight undergarments will just make you sweat indoors, which will make you cold outdoors. You can spend $15 each piece at Walmart or $80 each piece at the yuppie outfitter stores. Doesn't seem to matter all that much.
Wear your regular summer gear over your street clothes for insulation. Avoid 100% cotton. The air spaces in the mesh, armor, and textiles of gear allow good air movement around your body, redistributing heat and moisture from warm and damp areas to cool and dry areas, limiting any build-up of perspiration that would turn to ice in a breeze, and the air spaces provide good insulation. Win-win!
Invest in high quality rain gear with an emphasis on wind protection, ventilation options, and durability. Avoid insulation as its presence will quickly eat up storage space and limit the gear's versatility in mild weather. I wear the same Nelson Rigg rain gear year around, 7*F to 112*F. I've had mine for years, incuding 46,000 miles when Tdub was my only transportation. Rain gear is an excellent windbreaker, and turns everything underneath, especially armor, mesh, and textile, into insulation. In all but the coldest weather, a rain suit can be replaced with a $25 synthetic jacket from Walmart, sized to fit over your gear jacket.
For your feet, consider a pair of waterproof high-top work boots a bit too big. Tight footwear limits circulation, causing cold feet. Wear wicking socks and synthetic thermal socks. If you prefer safety toes and shanks for protection, seek the composite type as steel wicks heat out of your feet at a rapid pace.
For your hands, consider wicking glove liners, your normal gloves, and an effective means of blocking ALL the wind off your hands. Hippo Hands or boots as shown in the pic above will get the job done. Brush guards will not. Hippo Hands are overkill and expensive, boots look funny. Make a set of wind guards yourself. One can use a thin piece of lexan for shape sewn into any waterproof fabric. I've made a temporary set from gallon milk jugs and duct tape that worked quite well, actually. I've also made some from a cheap polytarp and duct tape, shaped with a frame of piano wire. Cheap and effective, but ugly.
For your head, try a full-face helmet. A small cork used to make lamps not scratch tables stuck between the bottom of the visor and chinpiece cures most fogging problems. On a 5-minute commute, a bit of chin and cheek may be exposed and a bit uncomfortable, but exposure time won't be long enough to be a health threat. One can always add a neck gaitor if necessary.
Using this system, when you arrive at your destination, strip off the rain gear and wear your regular gear inside.
If you plan to ride some distances, adding an additional layer of insulation head to toe will contribute to comfort. I'm partial to 100% polyester fleece and acrylic knits as additional insulation because they are reasonably priced, stay effective when wet, and are wash-and-wear. Adding heated gloves, grips, and/or socks, but TWs are not blessed with a plethora of amps, so those options are limited. A few dollars of chemical hand warmers in boots and gloves will take you a long way.