1) Yeah you'll find couples sitting around campus pretty often. When it comes down to dating Loomis is pretty much like any other normal school.
2) Usually teachers will use percentages that convert into a GPA on the scale of 4.3 (which is an A+).
3) I'm a new sophomore but I adjusted pretty easily, so for a freshman it should be easier since the social circles haven't formed yet. Honestly the best way to make friends is to just be yourself and socialize. Don't be shy and join whatever your interested in, whether its a sports team, theatre, clubs, or music.
4) The dorms are pretty big. Typically there's room for a desk, mini-fridge (

), wardrobe, closet, couch with a good amount of room left. Some dorms have larger rooms than others, but you shouldn't feel at all claustrophobic while your in your dorm.
5) There are singles, doubles, and triples. My dorm has mostly singles with a couple doubles. Some dorms have a mixture and some have mostly singles.
6) There's a dorm bathroom on every floor with two showers.