You're on the right track hitting the Keys. Other stuff:
South Beach in Miami Beach. Do Lincoln (Place, Street, Ave, whatever it is) in the evening there. Niether SoBe or the Keys are for the economy minded. Things are spendy there.
Fort Desoto Park in St Pete.
Maybe Clearwater Beach in (duh) Clearwater.
Do A1A in the Flagler Beach area, old Floriduh. Stay at Symphony Beach Club in Ormond Bea, get an ocean front room, preferably above first floor. Frank and Carmen run it and are a delight. Frugal rates, especially for the ocean
front. There is a place called the Schnitzel House up the roda from them. Yummy Yurapean food.
Also, figure on at least a day in St Augustine. Eat here:
http://www.tripadvisor.com/Restaurant_Review-g34599-d390356-Reviews-O_Steen_s_Restaurant-Saint_Augustine_Florida.htmland/or here:
http://www.a1aaleworks.com/and/or here:
http://www.hookedonharrys.com/page/28-4172.htmThe area north of Orlando/Tampa has the best riding in peninsular FLa. Think Lake, Marion, Levy, Alachua, Pasco, Hernando counties, plus more. Other favorites for one off type places to eat, in above area:
this is my absolute most favorite restaurant, the atmosphere is killer. Watch for the limited hours and sit close to where Rick Green performs.
http://www.yearlingrestaurant.net/Also hit Sleepy Hollow near Floral City. Bonus, it's on a very marvey road
http://www.wallowatthehollow.com/--------------
In general stay off the main highways and freeways, and definitely avoid Us 27 between Clermont and Sebring, there are about 58 traffic lights, lotsa big trucks, Snobirds and it's ugly. Unless you want to hit a coast on the way up, come up the east side of Okeechobbee. Pleasant riding.
A cold snap can hit at any time pretty much through April, January generally is a bit brisk except for being perfect in the Keys. Highs here in Lake county average upper 60's in January. Rooms would be easier in January for spur of the moment type of itinerary. (My way to travel)
HTH.