Hi all. Newly engaged and working on developing a budget and guest list. We are probably honestly looking at $10K or less, and I know our guest list size affects that by a lot. FH and I fully know that we simply cannot have a 100+ person wedding, and we tend to prefer smaller crowds anyway.
I have a large extended family -- my aunt and uncle have 6 kids, and 5 of those kids have families with anywhere from 3-5 kids themselves. I grew up being around my cousins all the time, but in total honesty, I just don't think we can afford to invite all of them. My part of the guest list goes from 51 to 20 just by only inviting my aunt and uncle

I do feel like my cousins would understand, btw. We are not doing adults-only because our own 4 yo will be there, I want my nieces there, etc.
For those of you with large families and lower budgets, what did you do? Is it rude to only invite my aunt and uncle? If it matters, my cousins are all adults, and we are leaning towards a small wedding and then having a large lunch or party (that doesn't come with the wedding premium) for everyone later on. I know it's our day, but I also don't want to hurt anyone. Thank you!
Re: Large families... etiquette, not inviting cousins?
The only thing to be careful about would be if you were inviting some but not all cousins. It's still not an etiquette blunder, but you risk hurting feelings when you invite some but not all.
I have had more first cousins who invited me, but not our kids. Also totally okay and understandable.
It's the circles thing. It's okay to say that you and your siblings get to bring their children, but your cousins don't. Some of them may not want to find childcare and will decline, but it shouldn't be offensive, as long as all the cousins get the same treatment.
It is absolutely appropriate to decide to have a small wedding and reception.
I'm not really clear on what you meant by the bolded statement. What would not be appropriate is to have a second, "non premium" reception on another day for those not invited to the wedding.
However - say my cousin doesn't invite me to his or her wedding, I'll probably be like, "Cool, fine, makes sense, it's not like we're that close." But if I'm not important enough to you or you to me for me to make the cut for the actual wedding guest list, there is zero chance I will prioritize a mere party in celebration. If it's in town, and I don't have other plans, sure, but otherwise I won't bother. I think people overestimate how much most people really want to be included merely in anything wedding-adjacent.
I know someone two different people who planned out of town weddings so that they could send the invitation to all 300 people - but would only have to pay for a 50-person reception, and then those other non-attending people would be expected to go to one of the lower-cost, non-premium "gift collection"/"wedding adjacent" parties. One of those people had THREE gift-collection parties because she had lived in three parts of the country.
Here is an acceptable after-wedding recognition: If your family or his family are ALREADY having a family event... like if the whole family is going to someone's house for Thanksgiving or July 4... someone could give a toast to you newlyweds. Or you could host a party - NOT for you but for a regular holiday celebration - and someone could give a toast to you. But you can't host a separate wedding reception after the REAL wedding reception.
TBH it helps that we're having a destination wedding with very limited venue space so it's an easy justification (immediate family and close friends only). We're still at close to 100 people invited but that's just how large our families are. We're also having a "sequel" reception back in our home town and so we're throwing the extended family invites to that. FWIW, at least where I live, it's cheaper to rent a castle in Scotland for 3 days (including airfare) than it is to have a single-day wedding here. DC's the worst.