Is specializing in inviting non-Muslims to Islam more greatly rewarded, or is speaking a word of truth to a tyrannical ruler more greatly rewarded?

Capabilities are blessings that necessitate gratitude to Allah by using them in ways that benefit the religion. Calling people to Allah with wisdom and good counsel is among the greatest acts of obedience, and its far-reaching benefit yields greater reward. Speaking the word of truth is required with wisdom and knowledge and is not limited to confronting an unjust ruler. The benefit of calling people to Allah is general, whereas the benefit of speaking the word of truth to an unjust ruler is often limited to the speaker. It is advisable to busy oneself with acquiring religious knowledge that qualifies one for calling people to Allah, especially non-Muslims, instead of entering into confrontations that may be unbearable. It is also recommended to focus on purifying and reforming oneself.