Yank
Bulbous Also Tapered
Canned tomatoes? You need fresh, well ripened tomatoes above all else. They should be peeled, seeds removed, and chopped. Get that right, and you wont need to add sugar or acid to correct the failings. Ideally use the long Italian tomatoes, as they contain less seeds.
Canned San Marzano roma tomatoes can make a better sauce than most grocery store fresh tomatoes, unless you've got access to an exceptional garden or farmers market. And canned is the only choice when tomatoes aren't in season.