Traveling from the US to Costa Rica for Thanksgiving

Are there things to be aware of that I might have missed from other sources or misunderstood from the embassy page?

Yes, but what you missed is quite minor and likely doesn't affect you (ban on some flight paths, unclear if they'll still be present in November). See bold points below from https://www.iatatravelcentre.com/world.php (-> Costa Rica):

Costa Rica Published 15.10.2020

1. Passengers are not allowed to enter.

• This does not apply to:
• nationals and residents of Costa Rica;
• passengers who do not require a visa to enter Costa Rica when traveling as tourist if in the past 14 days they have not been to any other country than Australia, Austria, Belgium, Belize, Bulgaria, Canada, China (People's Rep.), Croatia, Cyprus, Czechia, Denmark, El Salvador, Estonia, Finland, France, Germany, Greece, Guatemala, Honduras, Hungary, Iceland, Ireland (Rep.), Italy, Japan, Korea (Rep.), Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Monaco, New Zealand, Netherlands, Nicaragua, Norway, Panama, Poland, Portugal, Romania, San Marino, Singapore, Slovakia, Slovenia, Spain, Sweden, Switzerland, Thailand, Uruguay, United Kingdom and Vatican City (Holy See) [enjoy the triple negation! good way to inform travelers];
• residents of the following states of the United States: Arizona, California, Colorado, Connecticut, Florida, Georgia, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New Mexico, New York, Ohio, Oregon, Pennsylvania, Rhode Island, Texas, Vermont, Virginia, Washington, Washington D.C. and Wyoming;
• family members, who do not require a visa to enter Costa Rica, if traveling as tourist and who are:
• spouses of nationals or residents of Costa Rica; or
• parents of minors who are nationals or residents of Costa Rica; or
• children and siblings, who are minors or with disabilities, of nationals or residents of Costa Rica.

2. Flights to Costa Rica are suspended.

• This does not apply to:
• flights arriving from Australia, Austria, Belgium, Bulgaria, Canada, China (People's Rep.), Croatia, Cyprus, Czechia, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland (Rep.), Italy, Jamaica, Japan, Korea (Rep.), Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Mexico, Monaco, New Zealand, Netherlands, Norway, Poland, Portugal, Romania, San Marino, Singapore, Slovakia, Slovenia, Spain, Sweden, Switzerland, Thailand, Uruguay, United Kingdom or Vatican City (Holy See);
• flights arriving from the following states of the United States: Arizona, California, Colorado, Connecticut, Florida, Georgia, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New Mexico, New York, Ohio, Oregon, Pennsylvania, Rhode Island, Texas, Vermont, Virginia, Washington, Washington D.C. and Wyoming; [check with Costa Rica embassy + airlines whether it'll change on November 1]
• repatriation flights.

3. Passengers traveling as tourists must have a medical insurance to pay for Coronavirus (COVID-19) treatment costs. The insurance must be issued by a company in Costa Rica or approved by the Costa Rican Institute of Tourism.
4. Passengers traveling as tourists must have a medical certificate with a negative Coronavirus (COVID-19) RT-PCR test result, taken at most 72 hours before departure of the flight to Costa Rica. The certificate must be in English or Spanish.

• This does not apply to:
• nationals of Costa Rica;
• family members, who are spouses of nationals or residents of Costa Rica;
• parents of minors who are nationals or residents of Costa Rica;
• children and siblings, who are minors or with disabilities, of nationals or residents of Costa Rica;
• passengers younger than 12 years.

5. A "Pase de Salud" form must be completed at most 48 hours before departure of the flight to Costa Rica. This will generate a QR code which must be presented upon arrival. The form can be obtained at www.salud.go.cr/
6. Residents of Costa Rica must have proof of payment of the Costa Rican Social Security.
7. Passengers could be subject to self-isolation for 14 days.
8. Entry regulations for nationals of Costa Rica apply to passengers with proof of being dual nationals of Costa Rica.
9. Passengers must arrive at San Jose (SJO) or Liberia (LIR).
10. Expired residence permits (DIMEX):

• with category “permanente" are extended until 11 January 2021;
• with categories “temporales" and “especiales" which expired after 18 December 2019 are extended until 11 January 2021;
• with category “estancias" which expired after 17 March 2020 are extended until 12 February 2021.

11. Effective 1 November 2020 passengers who in the past 14 days have been in any state of the USA will be allowed to enter.