Many people pay more attention to the color of the lenses, but there is much more to it than that. VLT stands for Visible Light Transmission. The sunnier it is, the lower VLT percentage you will want. As you may have guessed, the more overcast it is outside, the higher the VLT percentage you will want.
Unfortunately, there is not one goggle that fits all. Many avid skiers have multiple goggles for different climates. However, if you are looking to only invest in one pair, a pair with a VLT of about 30% will be a decent pair. For extreme conditions, they won't be ideal but for most days, they will be great!