I do not think you require a child for the purpose of example. You had one child, and by the desire of Krsna the child did not stay. Now you can forget of any child. Just do the present service with great care and affection, that will be your best service to Krsna. Better to accept Krsna as your child, and He will never leave you like material child. He will stay with you forever.
For raising children in Krsna Consciousness, you will get many opportunities to do so. When I was householder, I was just taking care of one or two children, but after retiring from my household life Krsna has given me chance to raise so many nice children for raising them to Krsna Consciousness. So instead of desiring to raise a bodily child to Krsna Consciousness, if you stick to this service, Krsna will give you many children for that purpose.
I am so glad to hear of Hamsaduta's determination to become Krsna Conscious. The determination is difficult, Krsna Consciousness is not difficult—Krsna Consciousness is natural. One knows how to love another, so instead of loving so many others, one can very easily take to the business of loving Krsna—this is determination. That much is required, otherwise Krsna Consciousness is not difficult.
Regarding your question, a sinful person, never mind what kind of sinful man is he, is taken in subtle body to the place of Yamaraja, and there he is trained up in a particular type of suffering. As soon as he is trained up, he is given a particular body by which he can endure such sufferings.
You write to say that you look forward to that day when sense gratification will become simply insignificant, and yes that is the stage of pure Krsna Consciousness when our only desire is to be serving Krsna with no personal considerations whatsoever.