Hey guys! I’m a rising senior working on narrowing my list of a whopping 16 colleges because I don’t want to stretch myself too thin applying to so many. I visited a handful already (and had camps in a few), but I have a problem: I love every single one. I admire the modern campus and co-op program of Northeastern, Harvard makes me feel at home, I love the teeny compact campus of Tufts, right next to home and a medical center, and Dartmouth has something about it that I can’t put my finger on, etc. etc.
I’m visiting other schools this week, and I’m terrified that I will love them just as much as the other ones. How am I supposed to choose which not to apply to?? If I take them off my list I will always wonder “what if”…
The schools I like are all really competitive (minus my safeties) and I doubt I’ll get into ALL of them and have to choose between them, but does anybody have any advice? What other factors should I consider other than size, location, and programs that might turn me off from some of my choices? Thank you in advance! 
Definitely run the NPC and see what they are likely to cost, and talk to your parents about what you can afford. Compare your GPA and SAT scores with the 25th and 75th percentile for each school and look at the % of applicants who are accepted to try to guess your chances of getting in.
My daughters did both know students who applied to 16 or more schools. We thought that this was a bit much (both daughters applied to somewhat fewer than this).
Other factors to consider - cost of attendance and merit scholarships
Are you in love with your safeties as well?
This is a great problem to have! Definitely look into campus life and student stress and satisfaction. Look into extracurriculars you might be interested in, look through the labs and research projects students and faculty are working on (applies to STEM and humanities). As for stretching yourself too thin, look into how many of your schools even have supplements - for example, Northeastern has no supplement. You could also just see which schools’ supplements you are most excited to write and go by that.
Things like…
Academic calendar - semester (Tufts and others) vs quarter (Dartmouth)
Academic focus - undergrad teaching (Dartmouth) vs. research focus (JHU) vs. pre-professional (Penn)
Curriculum - Core (don’t think you’re looking at any in this category) vs. distribution (Dartmouth and others) vs. open (URochester almost)
come to mind. But more importantly, I would think about think about fit. IMHO, the typical Dartmouth student is very different from the typical Harvard or Hopkins student. That should play a pretty big factor in where you choose to apply (especially ED).
I’m a mom but totally get it . . . loved something about every college my son visited too.
eta: Forgot to answer your question! I would first try to rule out any and all financial considerations. If there is little likelihood of merit or need-based aid, and the school is just too pricey for realism in your life - let it go.