If the most vile person to live truly turned to christ and repented they will find heaven. It is not up to you to decide who christ saves in the end.

It is simply above your station to make such judgements

That follows the logic of subsituation.

I agree the doctrine is flawed. Jesus Christ brings a kingdom to mankind, a faith to overcome the present evil in the world.

I believe in God 100% but it's hard not to see Jesus as a Santa Claus figure for me personally

Jesus Christ is not portrayed well by the carnal church. The church in Christ is a spiritual active body that follows Jesus Christ as king.

Ah, no. Let me say it more strongly: "*May It Never Be!" Jesus has a way of ensuring that some fruit of repentance will be seen -and not just by Him. Even the thief on the cross changed from mocking Him to defending Him at a point in time (with the other one as a hostile witness) - and the Persecutor Saul became the Apostle Paul!

That same Paul answers "GOD Forbid!"! to the question you propose: Romans 6:

What shall we say then? Shall we continue in sin, that grace may abound? God forbid!. How shall we, that are dead to sin, live any longer therein? Know ye not, that so many of us as were baptized into Jesus Christ were baptized into his death? Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life.