Is traveling to Saudi Arabia with the intention of distancing oneself from tribulations (fitan) and drawing closer to the holy sites better, or is remaining with irreligious family members to try and guide them better? And will praying for them from afar benefit them in their lives and after their deaths?

There is no harm in traveling with your husband or remaining in your country. The consideration is what is most likely to encompass the greater religious and worldly benefits. The call to one's family is not prevented by being far from them, as there are multiple means and various methods for it. Among its greatest causes are seeking Allah's help, being good to those being invited, and persistent supplication without rushing the outcome. Righteous supplication benefits in all circumstances, for the near and the far, the living and the dead.