How often do you/will you fly JL?
Getting status on the airline you fly most and/or of your country is usually best. Easier to get credit card ff miles with a cc from your home country.
The AS "own flight segments" is hard. Those airline that still have this requirement often only have 4..
Do not take the airline operations and airline ffp as one and the same.

JetBlue is an AA freq flyer partner. Good range of B6 destinations from SJU. More than AA
https://en.wikipedia.org/wiki/Luis_M...tional_Airport

BA-IB-IE-QR(Qatar) all use avios as a ff currency. Subject to t&c's can move (at no cost) avosi from one airlines ffp to another airlines ffp

Objectives from a ffp?
Flying international business class status does not give much extra.
-->Deciding on a Oneworld Frequent Flyer Program? Help is here.