Veggies to start now outside?

I think I will go ahead and start some veggies in plastic boxes,to transplant later to cups, to control for weather. I was thinking of lettuce of course, but wonder what you all think about beets and peas? I have heard they don't like to be transplanted, but I have struggled with too wet, too warm, too cold etc the past 2 years. I did not get good crops, in the case of the peas, no germination at all; and see this as way to control for conditions - as blomma said in another post -can move and or cover as needed.

Radishes I'm getting ready to plant , they grow all right here , they will come up on their own when ready , early , easy usually .
Lettuce will frost burn below 20 degrees , When it stays above freezing for them , as doing here ,
My onions are showing signs of life so a week or two those also I will try .
Have you tried germinating the peas in the fridge , on paper towel , (yes Deno method )
If you set the root sprouts out on a 40 degree day , or with warmer earth raised in the garden , it seems to be the same as not moving them ? Try a couple in succession to teach yourself when to plant out ?
Peas are such a small plant to start with , stringy stems , at least as far as when I have tried them . Which has not been often ,

First are peach tree cuttings, Working early making a watermelon set , onions starting to show green

With onions doing that and figuring the Spring moves north at five miles a day .
I would think 3 or 4 weeks for you ? , as to your zone . The supposed frost free here is April 15 average . Still does often after that here , but as you are saying your cold weather greens take frost and even taste better in the cold weather .