God as viewed through a crime and punishment model

One thing that has always bothered me about christianity is the 'eternal damnation' idea. I've roughly been brought up on the ideas that if we sin, we go to hell (eternal damnation), and we're all sinners hence will all go to hell, unless we believe in Jesus in which case we go to heaven. I've also been told that God is loving, just, and 'a father' type figure. The problem is, I just can't reconcile these.

First of all, let's look at the father side. If your child does something wrong, you'll want to punish them. The main reasons for this are so that they learn right from wrong and don't do it again. Hence you tend to make sure the punishment isn't excessive for the crime committed. So if for example my son disobeyed me repeatedly I might tell him off sternly, then maybe send him to his room for a bit, etc.; I wouldn't send him out of the house and put him up for adoption and basically cut off all contact with him however. The problem is eternal damnation for sin (which presumably has a low enough threshold that it catches people who only sin from time to time, as opposed to nearly all the time) is giving an extreme version of the death penalty for such things.

Secondly, the issue with God being just. In almost all legal systems/society's crime+punishment systems, the punishment handed out will vary (similar to the father situation previously mentioned). The punishment for theft is likely to be lower than the punishment for murder, for example. There are several reasons for this - firstly, it would seem far more unfair to execute anyone caught stealing compared with people caught murdering others (where it may be seen as justified, but that's a topic for another day). A petty thief who steals a couple of dollars would hopefully be able to turn their life around, and certainly wouldn't deserve to be killed for that crime. Secondly you have the deterrant effect - if you put the punishment for stealing as equal to murder (e.g. life imprisonment or death penalty), then someone who steals has little to no deterrant against also killing people. So to avoid being caught committing a petty theft they're going to be much more likely to kill someone who sees them, or just kill someone to steal their items, meaning the legal system ends up encouraging the worse types of crime. The problem with christianity as I understand it though is that there is just the one extreme punishment for everyone.

Thirdly, the idea of God being loving (which also ties into the father figure). This would suggest that God would want us to 'be good', and would also not want us to be eternally damned. Now with your average person they're likely to be risk averse. In other words if you have a crime with say a $10k fine, and a 10% chance of being caught, they'll be deterred more if it becomes a 20% chance of being caught and a $10k crime than a 10% chance of being caught and a $20k fine. In other words a greater certainty about the punishment faced for committing the crime is more effective than a greater penalty for that crime. However in the case of christianity you have uncertainty about whether you will be 'caught', with as big a penalty (eternal damnation) if you are caught. You could have a much better deterrance effect if you decreased the uncertainty about whether you would be 'caught'. If God is loving, then why would he not look to increase such certainty by say providing more evidence of his existence? For some people no amount of evidence would likely be enough, but for others it would be, meaning that the 'uncertainty over being caught' would decrease the more evidence was provided, meaning more people would believe in God and avoid eternal damnation, which I'd have thought would be wanted if God was loving. It also raises the issue of why equality (where people are treated the same, something that is usually critical for a legal system if it is to be seen as fair) since some people are given more evidence than others (e.g. a Jew around the time of Jesus who got to see various miracles performed would have had more evidence than say someone born today)