We had a relatively modest ceremony - about 40 people at an upscale Palm Springs hotel on a Sunday afternoon with a band, catered food etc. - and honestly, although it was a good time, I actually think if money's such an issue that holding a potluck/byob event is even a thought in your mind, you should just go to the courthouse and host a vow renewal later.
We spent about 10k, far below the average, and honestly I think in hindsight it would've been much better to do the courthouse and go to a nice restaurant with family afterward (even if there were 10 of us at one of the nicest spots in town, this would've cost a fraction of what the wedding did), and go on a very nice honeymoon.
This is definitely your decision btw, I'm just chiming in as someone who wanted a nice wedding, threw a nice wedding, and actually thinks the money could've been used better elsewhere. I feel like I'm not the only person who feels this way, but that women especially have trouble admitting it.