On our ride the other day my husband's fingers got a little bit cold (mid 50s F, partly sunny). He was using full finger gloves, they are not insulated but do block the wind. His fingers got cold and I was thinking that something like "glomitts" (fingerless gloves with a mitten section that flips over the fingers) might have been useful. He was having trouble with zipper pulls and using his Garmin with gloves on.
The biggest thing that has made my fingers cold in gloves is resting them on the brake levers. The metal just sucks the heat out. With the upright configuration of my recumbent handlebars, I can ride along ready to brake but not have my fingers touching the levers. My fingers had to touch the levers on my old Trek.
When it is cold enough I use Ibex "Knitty Gritty" wool gloves, a wool blend with rubber grippy stuff on the palm and fingers. They are not padded, but are warm enough for my California Central Valley winters (not lower than 35 degs F).
I tried some fancy neoprene winter bike gloves to try and keep my hands dry but they ended up acting as a miniature sauna for my sweaty hands and I nearly froze my fingers off.
I generally don't ride in the rain, although the wool gloves are sufficiently warm in light rains down to about 40 degrees.