Hello,
New here but would like to say on the Old/New salvific-

Old Covenant “salvation” is a promissory note
New Covenant “salvation” is cash
“Cash” is easier to understand because we don’t exactly know where the “money” will come from to pay off the “promissory note/debt”.

To me one of the biggest hurdles facing Grace based salvation is when someone tries to turn it into license. Grace does not equal license, but Armenian types are accusatory in this respect. The same grace/license idea snared/snares many. Reality of Grace is that desire to satisfy the will of our Redeemer above any other. Realistically we are growing in grace and if we could hit the mark every time then we would be able of our own accord.