@Wayne I also sometimes freeze whole tomatoes, but I never freeze peppers since they are good here almost year round (the only time they aren't good is in the peak of summer since the excess heat makes then bitter).
Tahini is a very common addition to shakshuka in Israel. Merguez sausage are also common. Eggplants and feta are less common.
To me however, tahini is a must.
Caraway is a Tripolitan (or Libyan in general) addition. It is not very common Israel and should not be overly strong in the final dish. I include it about half of the times.
I will also note that shakshuka can be made with a long range of cooking durations, leaving the tomatoes anywhere from barley cooked, firm and a little acidic, to slow cooking, bringing deep and rich flavors.