I believe non-immigrant visa applications get denied or delayed for two reasons:
1) National Security concerns
2) Inability of the applicant to prove that they will return home w/o overstaying their visa
While there is no easy solution for the first issue, I believe the second issue has a solution: Give consular officer discretion to require the visa petitioner to post bond.
Bonds will be refunded in full when the petitioner surrenders the visa.
I believe this system will improve business climate allowing companies to have people over here for business related travel without worrying about them being denied visa.
I also believe this will improve tourism to the US and create jobs.
Tourists are denied visas every day because of their inability to prove they don't have immigration intent.