below are the exact sizes for uploading images to each content section. However you can upload larger sizes the system will automatically resize to a set width while maintaining the images aspect ratio. with the exclusion of the three image section, these must be uploaded with specific width and heights. 

However yes uploading the precise sizes across all sections will produce great results. 

The width of each image in its respective sections are:

hero image: (750 px)
product gallery 4 images (150 px)
product gallery 3 images (203 px)
text with full width image (750 px)
One image (750 px)
Two images (365 px)
Image right (430x380), 2 images left ( 300x180)
Image left (430x380), 2 images right ( 300x180) 
text left, image right (300px)