A time to be born and a time to die

So I'm probably blogging too often these days for people to keep up, but I've been thinking about all this stuff recently, and last night I came up with so many questions, I had to write it all down in some kind of logical order...

Questions:

• Is a new soul formed at the moment of conception? Or do souls already exist infinitely in eternity, and "insert" themselves into a body at the right time (presumably at the time of conception)?
• Assuming all souls incapable of forming a decision about whether they want to follow Jesus are saved - does this mean that technologies such as IVF and stem-cell research contribute to the expansion of the kingdom of God? (The reasoning behind this being lots of new embryos being created and destroyed = lots of souls incapable of making an informed decision about salvation = lots of people in heaven.)
• Do we have the equivalent of earthly relationships in heaven, i.e. friends, brothers, sisters, cousins? Even if we don't, will we recognise the people we had relationships with on earth? What about the people who never had a chance to be known by anyone? (Sorry, this is going to be a rather pre-natally focused post.) This also goes back to a question I posted a few days ago - what will our resurrecton bodies look like? What age will they be and will they be recognisible as us? Would you be able to recognise someone who died as a baby?
• Does the soul of a senselessly created (and aborted) embryo have equal value to God as the soul of a mature Christian person, who has undergone persecution and trials, tests of faith, development of character, etc?
• Say one assumes yes.
• Is this unfair?
• Is it fair that the person who ran the marathon of a long godly life should have the same eternal fate as the person who made it halfway down their mother's left fallopian tube?
• Or are we rewarded according to what we've done on earth, during our life "under the sun"? What if you never made it to life under the sun? How then can we be equal in God's sight?
• How then can there be such thing as eternal justice?

So I guess I am questioning the existence of the eternal justice we as Christians expect to happen on that day. Please don't stone me yet. I'm just curious.