We have breakfast in our room most days (yogurt, fruit, cereal and milk) and have high protein snacks (cheese, nuts, jerky) for taking into the parks. Honestly, we're usually so busy in between meals that we don't snack often.
I also have things to make sandwiches in my room for times when we're hanging out/resting and someone wants more than a small snack. A quick turkey/cheese sandwich and a few chips from a big bag saves cuts back on hunger and saves money compared to running down to quick service (even when ordering sandwich fixings from Garden Grocer).
We eat TS at least once a day, but even the biggest eaters in our party often share. We'll share a bunch of apps among us and each get a salad, or each get our own app and share an entree, or just flat out share an entree without an app depending on where we eat (I find portions at many WDW TS places to be huge). If we're eating at a new place, I just look here on Dis to see if the place we're eating is one with larger or smaller portions.
We also share at TS places. And as noted above, a few will get meal with fries while others will get a sandwich without, and we share.
How we eat usually depends on our schedule. If we have a night-time TS ADR, we snack throughout the day (breakfast in room, share a few QS meals, get a pretzel here and ice cream there) and are well satisfied. If we have a lunch ADR, we find that we're full long after (even when we share food) and just snack that night...again, sharing QS meals or snacks, getting a pretzel or piece of take out pizza, etc.