It sounds like you approached the wedding from the perspective of "here's the checklist of amenities we need to provide our guests", which you modified by striving to ensure each line item was reasonably priced. Not a criticism - I did that to, and for both of us it seems to have been a financially responsible decision.
However, for people for whom that isn't financially responsible, I'd suggest that that mentality isn't appropriate. The question shouldn't be "what do the guests absolutely require?", but "what can we afford? and what do we want?" In that order!
The bare minimum for a wedding is a court wedding. There are some reasons why that may not be the best idea at scale (that is, it may be individually appropriate but there are social reasons why that's not ever going to be the only sort of wedding). From there, the next thing you need is somewhere to gather some people. Are you really obligated to feed them? Depends on the time you pick. Are you obligated to rent a hall rather than find somewhere you can go for free? I'd say not. Do you need flowers scaled to the number of guests? Not really need, no. etc.
Given the ability of money issues to tear marriages apart, I'd say a new couple should strive quite hard to avoid debt for their wedding, and I'd say, get brutal with those costs. If social conventions are driving you into debt, screw social conventions. They were not, in the past, built for that purpose. To a non-trivial extent, they are built in the present for that purpose, and the answer to that is to not just decline to play, but to be angry at the people manipulating those conventions to put you in debt, just to ensure you stay in the right frame of mind. Plus if enough people do that, we can take them back.
"If social conventions are driving you into debt, screw social conventions." has application well beyond this particular matter, too.