I don’t think FAFSA is going to impact your OOS publics other than you’ll get access to a loan. Out of state publics, short of UVA and UNC which guarantee to meet need, don’t have a reason to help you need wise. They might - but I wouldn’t count on it.
Wisconsin - you love the surrounding are but you’ve not been to campus - do you know the area from prior visits? Otherwise, I’m a bit perplexed by the statement.
For UMASS - you have a variety of networking and internship opportunities - hmmmm - you don’t think you have those same opportunities everywhere? You do - hence today jobs are found on linkedin/indeed - but that’s not an advantage (or disadvantage) vs. others on your list.
So in state tuition for systems engineering at UIUC is $18K but room and board is $17K. Are you meaning all in is $35K? You say Rochester is $35K tuition but I want to make sure it’s all in - so that you are comparing apples to apples. So Illinois is tuition, room and board and so is Rochester.
So you didn’t share the Wisconsin cost but for tuition, room and board (without the extras like transport) is high 50s. Can you afford that? If not, easy to eliminate.
You say UMASS gave you $14K. So it’s $57K - so that makes it $43K for tuition, room and board after merit. You won’t have to worry about food there (you noted for Rochester) as they are top 3 in most rankings in the country. Can you afford $43K, if not easy to eliminate?
So you have - and please clarify on Rochester tuition - if you mean all in vs. just tuition.
Rochester - $35K
Illinois - $35K
UMASS - $43K
Wisconsin - $57K
You can wait for FAFSA but I’m assuming no need aid (OOS) and Rochester has your CSS so they already know and made an offer.
First cut - can you afford all four? Or do you parents want to afford? If not, eliminate.
As for Rochester or UIUC, different schools, different experiences, and different majors.
To me it becomes a question of distance vs. assuredness of what you want to study.
If you truly know you want CS, you should choose, in my opinion, Rochester. If you’re unsure (and college kids change) and the distance really troubles you (a short plane flight), then UIUC is viable.
If UMASS is affordable and you visit and like it, then you get great food, your major and a solid program. It’s college so you shouldn’t be going home each weekend but stuff happens. It’s also a short flight - but a little harder to get to the airport - but that’s not a reason, to me, to eliminate a school.
Best of luck in whatever you decide.