It’s not that simple. Scores are one of many factors that are considered at selective, holistic colleges. Some students get accepted with lower than average scores compared to other matriculating students, just as some students get accepted with relatively poor essays or LORs compared to other matriculating students. You may have a good chance of admission or a poor chance of admission, depending on the rest of your application and the specific school. Schools also have wildly varying degrees of selectivity, yield, and how they treat scores in admission. The average admit rate for applicants with your scores will often dramatically vary between schools, even if the score is in the same percentile of matriculating students.
For example, you mentioned that you are interested in Middlebury. Middlebury is test flexible and allows you to submit SAT II subject tests instead of SAT/ACT. Obviously ACT scores would be less influential if you chose to not submit them. Schools that have such test optional/flexible policies often place less weight on test scores when they are submitted. Middlebury’s CDS suggests this may be the case with Middlebury. Their CDS marks 6 other criteria as more important than scores. Test scores are also considered in the context of your application. You mentioned that you would apply to Middlebury as either planned Art History or Geography. Your scores are not well balanced (34, 34, 29, 25), so admissions will likely consider which sub-scores had the 34s, which had the 25, and how those subject scores relates to your prospective Art History or Geography major. They’ll also consider whether the rest of application is consistent with those scores. If the scores are part of consistent pattern that suggests a prospective math major is weak in math, then that will likely be treated differently than a prospective English major applicant who had a lower math ACT, but got an 800 on his math II and is straight A student in math, including in AP calculus.
You also mentioned being interested in Cornell Art and Architecture. The different schools at Cornell often emphasize different admission criteria, which can lead to treating scores differently. Some also have notably different scores averages than the overall average listed in the CDS. Art & Architecture requires submitting a portfolio, which can be a key factor in admissions. A student with a great portfolio and great rest of application likely has a good chance of admission with your scores. A student who has a weak portfolio and weak rest of application is likely going to be rejected, even if he has perfect scores. Some related quotes from Cornell’s website are below:
[quote=Cornell] Standardized test scores are only a small part of your application for admission. Let me say that again, standardized test scores are only a small part of your application for admission. SAT or ACT scores represent one Saturday in your high school career...
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Vanderbilt is known for placing a greater emphasis on scores than the vast majority of other selective, holistic colleges. There are also some less holistic colleges that almost entirely admit by stats. It’s not just a single admission system. However, you didn’t mention being interested in Vanderbilt or less holistic colleges, so this may not be relevant.