I don’t know the answer to the question about how important is it to submit a portfolio in portfolio-optional situations. I would think that if a school says it’s optional, then it’s really optional. You and your counselor could explain the reason that you don’t have an art foundation is that you were drawn to architecture late in the process, too late to switch your senior year schedule.
Your grades are excellent, your scores will be fine, you appear to be taking a very rigorous curriculum, hopefully you’ll edge into the top 10%. Choir/music is a solid EC. If you have another, that would be even better. I assume you’ll have strong essays and recommendations. So you’re good to go.
An EFC of $41K is a heavy burden, but as long as your parents are comfortable with it go ahead an apply to a few need-only schools. Right now you’re looking at a wide range of types – BArch, BS/BA architecture, BA @ LAC, UC/CSUs. Ideally you should have reach/match/safety and financial safeties within each category, but doing that would result in a very long list. I think you’ll have a better idea about architecture after your summer experience and after you visit a few LACs.
I don’t know too much about merit aid at large colleges, and everything I know nothing about merit aid for architecture school comes from posters on this board. You might post a separate question asking about others’ experiences.
I’m surprised that CalPoly’s architecture acceptance rate is that high considering its ranking. My understanding is that it’s a somewhat different environment than schools like Tulane, WUSTL or Cornell but who knows? That may end up being a plus for you.
Some academically rigorous LACs that offer good merit include Kenyon, Grinnell, Macalester, Davidson, Rhodes, Colby. Carleton to a lesser extent. I’d also look at Pitzer, where you’d have access to the other colleges in the consortium.
The more selective schools in the northeast like Brown, Williams, Wesleyan, Hamilton, Vassar etc. offer generous need-based aid. Run a few net price calculators and see how you do. You may be pleasantly surprised.
My impression is that summer architecture discovery programs are not terribly competitive (though they may be selective with scholarship money) so don’t worry too much about your references and application. Both Tulane and WUSTL are good choices. They’ll probably let you know early enough so that if you’re not accepted you can still apply to others.