I have some Sicilian sea salt but, unfortunately, it is combined with basil so I can't separate the two flavors. I also have some Baleine coarse sea salt from France. The Sicilian sea salt seems to have a smaller crystal size than the Baleine sea salt and can be reduced to a finer size by crushing it between your fingers. It's harder to do that with the Baleine sea salt. I think both salts are intended to be used more as condiments rather than as ingredients for a pizza dough. Certainly they can be used on top of a pizza as a condiment or in a sauce, but its utility in a pizza dough is much less clear.
I can confirm from my research that Una Pizza Napoletana uses Sicilian sea salt as a condiment for its pizzas but I have not been able to determine whether it is also used as an ingredient for the dough. There is no reason why the Sicilian sea salt can't be used in the dough also, but I think it may be a waste of a good--and expensive--salt that is better reserved for other uses.
All salts, whether they are ordinary table salt, Kosher salt, or sea salt (fine or coarse) are essentially the same chemically, being primarily sodium chloride. The differences are how they are produced and processed. The sea salts are harvested from beds through evaporation and have more minerals and no additives or anti-caking agents. So they are more natural (they can even have different colors and flavors) and may have a bit more mineral nutritional value but not necessarily a significant value over other salt forms when incorporated as an ingredient in a pizza dough. Ordinary table salt is usually mined from underground deposits, stripped of some of the nutrients during processing, and supplemented with additives (including iodides) and anti-caking agents (so that the salt crystals don't clump). It is not as natural as sea salt but it won't behave much differently from a chemical standpoint when used in a dough. Kosher salt has larger crystals (flakes) than the other two forms and is lighter than the other salts, and usually has no additives (although it may have anti-caking agents), but, again, its performance in a dough is not materially different than the other forms of salt.
I have read of tests that have been performed to compare the effects of all of the above forms of salt in yeasted dough products and the results seem to suggest that people can't tell the difference. My personal experience is in line with those test results. Even when I lay out all the forms of salt I have on a table and taste them, the differences are minor.
As for your tomato sauce "brightness" dilemma, have you tried adding red wine vinegar and/or lemon juice to your sauce? This is something that Peter Reinhart recommends in his book American Pie (he recommends 2 T. of the red wine vinegar and/or lemon juice for a 28-oz. can of crushed tomatoes).
Peter