(1) What is your home airport? BWI/DCA/IAD
(2) What types of fares do you usually buy ? Y
(3) How many miles do you usually fly each year? (<25K)
(4) Do you have any kind of status at present? What is it? (Avianca RedPlus)
(5) What is most important to you in a FFP? (Lounge Access is not important. Low-cost reward travel and upgrades on paid travel are our priorities)
(6) Which routes do you fly most often (US domestic, US--Latin America, Transatlantic to Europe)
(7) Preferred Airlines My in-laws live in Bolivia, so we prefer Avianca, CopaAir or AA/BoA because those are the only airlines with 1 stop service between WAS and VVI.
(8) Do you travel for work or pleasure? (Lesiure, perhaps one domestic US flight per year for work to attend a conference)

We take vacations in Europe or Latin America every year and we also visit my in-laws live in Bolivia at least once every year. Given the proximity of United's hub at IAD and the one-stop service to Bolivia available on Copa and Avianca, it seemed like it made sense to be loyal to *A, but I am still relatively new to FF programs, so I might be wrong here. For instance, I do fly BWI-BOS to visit my parents frequently (4x/yr), so I sometimes end up accumulating TrueBlue points with JetBlue, which is a partner of AA, and AA codeshares with BoA to offer one-top service to Bolivia from WAS. SouthWest also flies that route, so I also end up with RapidRewards points too. Neither my wife nor I flies much for work apart from a single domestic flight each year to attend a conference.

I also have no idea whether it makes sense to earn miles with an airline that I actually fly such as United or a Latin American carrier or whether it makes sense to earn miles with a loyalty program with an airline that we fly less frequently (if at all). It seems like a lot of people are using Air Canada Aeroplan, Turkish Miles&Smiles or Aegean Miles+Bonus FF programs without actually flying on those airlines all that much, but I don't know why.

We accumulate a large number of miles with our CapitalOne Venture X Card, but I don't think the transferred miles will help us earn any sort of status with any airline. Right now, we've been favoring Avianca because Copa is not a transfer partner with CapitalOne, but I don't know if there's anything else important that distinguishes LifeMiles from ConnectMiles. Complimentary Priority Pass is included with the credit card, so earning lounge access with FF miles is not important to us right now. It looks like partner reward tickets often require fewer LifeMiles than MileagePlus miles, particularly when it comes to flying TransAtlantic from Dulles to Europe, but at the expense of fewer available flights.