There's some clues about page size from some of the page previews. Chapter 1 is the Artificer, and Chapter 2 (character options) starts on page 23. With 20-something feats and 17 backgrounds, and 5 species, that's probably 21 more pages. Three adventures DMG style will only be about 6 pages. 20...
I'd say the sensory effect lasts as long as it normally would. Like, a spritz of perfume lasts maybe a few hours, at the most. But a wolf's growl would just happen and then be over. I'd rule that the smell moves with you. But that's just me. The Utility spells play better when they are used a...