Are your parents happy to spend $320,000 for four years of university with your taking any loans at all? If you have a bad semester or if you change majors late and it goes five years, are they okay spending $400,000, again without loans?
If the answer is “yes”, then I think that Colby is probably a reach but your list is reasonable. I would add U.Mass Amherst as another safety.
If the answer is “no”, then you need to consider the cost of your education.
A safety is a college that you’d be happy to attend if it comes down to it. A lot of kids spend time agonizing over the choice of their reaches, give a lot of time to their matches, and the safety is a snap decision. My advice is to spend enough time to be sure that if the cards go against you that you’d want one of the safeties and not regret you didn’t spend more time thinking about them. Only you can decide how well these are a fit.
I think that Reed may be better than a match, especially if you apply ED.
I also agree that Colby, with an acceptance rate below 10%, is a reach for anybody, and Northeastern is also likely a reach (though not a high one). You should, perhaps, look at a couple of other matches.
I have a question - why is Reed a “dream” for you? Reed is a little different from many of the other schools on your list, but if Reed is your dream, maybe the folks here can suggest some other schools you might want to consider.
My new college list:
Reach Colleges: Harvard, Yale, Princeton, Swarthmore
Match Colleges: Reed, Skidmore, Oberlin, Occidental
Safety Colleges: Stonehill, Quinnipac
Why Harvard, Yale, and Princeton? You seem to have a preference for Liberal Arts colleges, so why not populate your reach category with those? Liking Reed and Oberlin suggests Middlebury, Bowdoin, or Bates. Perhaps look at Pomona as a reach.
If those are truly your stats why not look at Williams, Amherst, Pomona, Uchicago, ect? There is a big jump from your reaches to targets. Those reaches are unlikely but other reach schools, as I suggested, are difficult but perhaps a bit more attainable. I also personally think that if you want your reaches to be HYP then you should add more reaches in general to your application. It’s a lottery at that level.
Other institutions strong in STEM to consider: Worcester Poly (WPI), Rensselaer Poly (RPI), Colorado School of Mines, Georgia Tech, Carnegie Mellon, U Rochester.