You seem to have your own ideas for what you want and don't want in your cream sauce for pasta. They're not my ideas, but so what? "De gustibus non disputandum," which translates as, "you're old enough to know what you want to eat." Wisdom and palate notwithstanding, you're the victim of bad technique. Let's see if we can't replace it with good.
First: Corn starch is the wrong thickener. It's wrong for wine, and wrong for the fairly rough handling you're dishing out to a dairy sauce. Ixnay the corn starch.
Here are five ways to go which rely on good technique. There are others, but these are the most basic.
Contemporary, straight reduction: Change the olive oil for butter. What made you think of combining olive oil and cream to begin with? Use whipping cream or heavy whipping cream. Add the wine and garlic to the shallots and butter, and reduce by at least 2/3 before adding cream. Do not add raw garlic directly to cream. Add the cream as the last ingredient and reduce at a simmer until desired consistency -- that is, reduce by about 1/2. (You can help the low-heat reduction process along by using a wide pan -- a lot of surface area speeds reduction. There's even a special shape called a saucier in French.) This will be a very rich, but still fairly loose sauce.
Traditional, egg (protein) thickened: Cook as above, but while the cream is reducing, break one egg for each cup of cream and beat them in a separate bowl. When the cream has reduced by about 1/4 to 1/3, reduce the heat to a low simmer; then (counter-intuitively) remove the sauce from the flame. Add a few tbs of hot cream to the beaten eggs to "temper" them. Then whisk the cream/egg mixture into the sauce. Return the sauce to the heat and whisk slowly and continuously until thickened. About 2 or 3 minutes. This is even richer than the version above, and nicely thickened. The term for using an egg this way is called "binding the sauce."
Traditional, bechamel variation: Change the cream for light cream (1/2 and 1/2). Proportion butter and light cream as follows: 2 tbs butter for each cup of cream. Saute the shallots in butter, add the garlic. Stir and when garlic becomes fragrant add 1 tbs flour for each 2 tbs butter. Cook the flour in the butter, at medium-low to medium heat, stirring frequently. The flour will at first smell raw, then as the smell disappears it will slowly change color. When the color becomes honey-blond, add the whine all at once. The wine will thicken all at once, and the mixture will look clumpy. Don't worry about how it looks, stir and cook until the raw alcohol smell disappears. Then raise the heat to medium-high and add the cream. If the cream is cold, you can add it in batches, letting it come to a simmer before adding more -- stirring frequently all the while. When all the cream is in, bring it to a boil, reduce to a simmer, and let it fully thicken -- about three minutes.
Traditional, veloute variation: Prepare the bechamel variation as above, but with the following changes: Replace each cup of cream with 1/4 cup of stock and 3/4 cup of cream. Add the stock after the wine, but before adding the cream.
Traditional, allemande variation: Prepare either the bechamel or the veloute variation as above. Meanwhile, in a separate bowl, beat one egg for each 2 cups of cream. When the sauce is fully thickened, temper the eggs, add them to the sauce off the flame, and finish the sauce at a simmer, whisking constantly -- as already described. When the sauce is fully set up you may add a little more wine. This will be a fairly stiff sauce with a fresh, wine taste.
With all of these, you might consider adding, after cooking, some fresh or frozen peas and some cooked ham cut in small dice, or crumbled, crisp bacon. The residual heat will be enough to finish them.
Hope this helps,
PS Cooking the flour in the butter as described in the bechamel, and as required for the veloute and allemande is called "making a roux (pronounced "roo.") This makes for a very smooth sauce. Adding the flour directly to liquid sometimes results in lumps; also, the flour does not cook as well.
PPS These things are legitimate techniques in Italian cooking and have Italian as well as French names. But (a) I don't know them, and (b) French is the lingua Franca of cooking. Who knew?