Q. This ceramic pot will be placed in full sun but could also go in morning sun as well. Clearly, I will not be able to remove the plant from the pot so looking for something fairly permanent.
A. I think the inside of this pot is about 15 gallons (nursery container) judging from the plastic container that is already in it. I don’t like to get into plant recommendations. It can get circular very easily. However, in your case I will make a recommendation.
Stay small such as the cold hardy citrus such as Kumquat (also spelled cumquat). As long as it’s getting at least 6 to 8 hours of direct sunlight each day, all fruit trees do well. They will stop flowering at less than six hours of direct sunlight. They will look fine but no flowers.
Two small, cold hardy kumquat varieties to consider are ‘Meiwa’ and ‘Nagami’. They will handle full sun as well, but they are originally from the colder parts of Asia so make sure the soil is appropriate with “organics” watered in. Of the two, I would recommend the ‘Meiwa’ variety because of the size of its fruit and its cold hardiness.