I hope I can get some suggested dates to plant the following veggies:
How early can they be put out?
Direct sow or transplant?
No rush on the broccoli, you want it to mature in cooler (late summer/ fall) weather. The others can be direct seeded when the soil is ready in early Spring. They'll germinate in cold soil & handle freezing weather.
You should check out the Winter Sowing (WS) forum. It's a great technique for getting those cold weather veggies started nice and early, all outdoors and NO growlights. It'll sound farfetched at first, but read the FAQ.
I'm in the Chicago area. I've always heard that peas can be sown outdoors on St. Patrick's Day, and that's when I've tended to do it. And it's a good excuse to go sticking your fingers in the soil in March.
I don't know that it's worth your while to do transplants, "winter sowing" or otherwise, for things like lettuce and spinach, although if you had an actual coldframe, I think a lot of people start their lettuce in those.
Broccoli or any cabbage family can be sown now using the Winter Sowing method. I have already sown a lot of flowers and some chinese broccoli since the middle of January. All the containers are out on the patio covered with snow right now.
Check out the Winter Sowing forum. I started winter sowing this year and I am having a great time this winter. :-)