Is excessive hesitation in financial transactions, extreme eagerness to repay debts, and avoidance of doubtful matters considered piety (wira') or obsessive doubt (waswas), especially when these matters are linked to hadiths like "Unlawful wealth prevents the acceptance of supplication"?

Whispers (waswas) are a great evil and must be guarded against. Praiseworthy piety (wara') is that which does not lead to extremism (tanattu') or the abandonment of permissible things. If a servant exaggerates in piety to the extent that they make life difficult for themselves and abandon what Allah has permitted without any doubt, then this is blameworthy due to the extremism involved.

There is no harm in accepting a gift, or accepting a wage agreed upon with a worker as long as they are content with it, or picking up dropped money as your property.

Piety (wara') is of three types: obligatory (avoiding what necessitates committing the forbidden), recommended (avoiding dealing with someone whose wealth is mostly unlawful), and disliked (avoiding legitimate concessions out of extremism).

The meaning of the chapter "He who did not consider whispers and similar doubts" in Bukhari is to explain the piety of those afflicted by whispers who refrain from permissible matters based on flimsy doubts.

A Muslim must fear Allah and seek lawful earnings as much as possible, such as not dealing with usurious companies and clarifying defects of a product when selling it, but without extremism or harshness that prevents him from accepting a gift or picking up his own money.