The curling is usually permanent. Just think of it as a Shirley Temple tomato plant.
You can put some mulch such as 2-3 inches of grass clippings on top of the pot to even out the drying. The pot should dry by the roots removing water. To get more air in you can take a stick and jam it down in 3-4 places halfway between the plant and the pot. I assume that you have pot shards in the bottom otherwise you could poke a stick up the bottom hole too. Personaly, I would probably dig a hole down at the side of the pot all the way to the bottom and stick my hand in to see if I had soggy mix at the bottom, but I've been known to screw things up just to get an answer. it would get air in thts for sure.
Nutrient problems/ root problems almost always affect the lower leaves first because the plant pulls things out of the oldest leaves for the new growth. Some deficiencies affect the very top leaves -- those nutrients that can't be translocted. A single upper or middle leaf yellowing has no normal explanation. Some soil born diseases can affect half a plant but you will see the leaves yellow from the bottom up. A middle leaf could get hit if no leaf was directly below it, but those diseases are rare in first year potting mix.
... so I have no clue what the yellowing is.