Why doesn't Krishna just bring everyone back to Vaikuntha?
It sounds like you're asking one question in several different ways.
By calling jivas "B grade creations of the Lord," you're basically saying, "why doesn't Krishna make everyone A grade?" Isn't it? That would mean that everyone was one. The idea that everyone is one with God is called Mayavadi philosophy.
"According to Madhvacharya, there are two tattvas, or factors. One is independent, and the other is dependent. The first tattva is the Supreme Lord, Vishnu, and the second is the jiva-tattva. Lakshmidevi, being dependent on Lord Vishnu, is sometimes counted among the jivas. The Gaudiya Vaishnavas, however, describe Lakshmidevi in accordance with the following two verses from the Prameya-ratnavali of Baladeva Vidyabhushana. The first verse is a quotation from the Vishnu Purana:
'O best of the brahmanas, Lakshmiji is the constant companion of the Supreme Personality of Godhead, Vishnu, and therefore she is called anapayini. She is the mother of all creation. As Lord Vishnu is all-pervading, His spiritual potency, mother Lakshmi, is also all-pervading.'
Lord Vishnu has three principal potencies—internal, external and marginal. Sri Chaitanya Mahaprabhu has accepted para-shakti, the spiritual energy of the Lord, as being identical with the Lord. Thus she is also included in the independent vishnu-tattva."
So there are only two tattvas (truths)—Vishnu-tattva and jiva-tattva. If jiva-tattva is eliminated, then all becomes "one." But Lord Krishna is a person—a supreme, eternal, blissful person—and He has loving relationships with everyone, even those who have forgotten their love for Him. These are the persons (us) who are looking for love in the material world.
Krishna is so kind that He offers each of us jivas the opportunity to try to find the love we want within the material world. This is so we can realize—come to our own conclusion—that the love we want is ONLY available in loving exchange with Krishna!
Lakshmi never has that illusion. She's always in love with Krishna, (Vishnu). She's always absorbed in His service. She's always thinking, "if my Lord is pleased, then I will be pleased." You're asking, "Why hasn't the Lord given us that position?" But first we must have the qualifications of Sri Lakshmi. It's because we have some personal desire that we're not qualified for that position.
You should understand that there's always opportunity for you to achieve that position. But to do so you'll have to do the work required to achieve the level of realization necessary to come to the loving relationship that the residents of the spiritual world, Vaikuntha, have with the Lord.
It's the nature of those of us in the material world to want something for nothing—to "win the lottery," so to speak—but in this case that's not possible. We must first become qualified, and THEN, when Krishna/Vishnu sees we're doing our part, He will reciprocate and bring us closer and closer to Him.
Actually, Vishnu wants us to come back to Him more than we want to go. He wants everyone to come back to Vaikuntha, but He wants our love. Love is voluntary or it isn't love at all. Love can't be forced; it has to be reciprocal. That means we have to come to the point of selfless love for Krishna. Then we'll be able to enter into that place of no anxiety— Vaikuntha—where there are only loving relationships with God.