I think the idea of a "basic cover" which also is a real good outdoor cover is unrealistic. A "good basic cover" is going to be a modestly priced cover used mainly indoors.
A cover which will give good protection and long life outdoors is not going to be cheap because, not only must it protect, but the cover itself must be durable, ie: you don't want to buy a new one every 18 months because the material gets degraded by the sun or weather.
I've used three kinds of covers over the years. Inexpensive units I bought at Costco (can't remember the brand) which were good for
indoor only, a Wolf cover which was indoor/oudoor (but didn't work well on my C5 Z06 because of the fixed antenna and the unacceptable manner in which Wolf has customers deal with making a hole for the antenna) and two covers from California Car Cover.
While Wolf and California Car Cover offer many of the same materials (Kimberly-Clark "Noah" and etc), I felt the manufacturing of the California Car Cover product was better, the manner in which CCC addresses fixed-mast radio antennas was far better and California Car Cover's customer service was better.
If I was going out today to buy another cover, I'd get it from Cal Car Cover.
Cal Car Cover