In some instances the federal statute grants standing to individual citizens (this is particularly true in the case of environmental legislation.)
Generally, a taxpayer does not have standing to challenge a federal expenditure. The exception is in first amendment challenges (e.g., where the expenditure was in the form of aid to education, that was to be spent through churches or religious schools - in those instances general taxpayers have been found to have standing to challenge.)
I do not know how you get standing or jurisdiction on the the Obama natural citizenship question. I think it (the idea of a President elected and inaugurated without being truly qualified) is an example of something so incomprehensible and unrecognizable to the drafters of the Constitution - that they did not address where the power to certify qualifications would rest in the organization of government. It’s an example of a problem which does not have a legal answer.
If that is indeed the case, then there is no reason not to grant standing in these cases. The court system is there to supplement those areas where there is a void in the law or where public officials have failed to enforce what is already there..
“It’s an example of a problem which does not have a legal answer.”
And I believe that this is why all the courts are avoiding it by claiming “no standing”. They don’t want to handle this hot potato.