Tips for your next party
I've planned for only a few parties in my life. This is a list I wish I had then.
Some favorites:
Advertise your start time as a quarter-to the hour. If you start an event at 2:00, people won't arrive till 2:30; if you make it 1:45, people will arrive at 2:00.
Most people will only go to a party where they expect to know 3+ others already.
Send the invites in chat groups (or visibly cc’ed emails) to clusters of 4-5 people who know each other, so they can see that their friends are also going.
Co-host parties with someone you like a lot but who isn't in your exact social circle, so that your two friend-sets can intermingle.
Figure out the flake rate in your social circles (the % of people who will RSVP yes and flake on the day), and set your invite numbers with that in mind. In my circles, consistently 1/3rd of people who say they will be there will actually not.