Different types of adverse items decline in scoring impact at much different rates. For example, many notice that the impact of 30-day lates appears to become minimal after a period of around 2 years, while the same is not true for major monthly delinquencies. Their continued impact, while also declining over time, is noticed by many to remain over the full 7 year CR inclusion period. Some observe that 60-day lates appear to be scored at the less significant impact of a 30-day late after a similar period of approx 2 years. Its a complicated scoring algorithm that changes in ways that are unknow to consumers as their bucketing profile changes.
Charge-offs are one of the more serious major derogs, in that they are a creditor statement that they considered your debt to have become "uncollectible." As such, their impact apparently does not deteriorate at as significant a rate.
Just how much is known only to the FICO gods. That is the bad news. The good news is that once it does drop from CR inclusion, it will most likely have a more significant impact than the exclusion of a monthly delinquency. You can still probably expect to see some score improvement.
Once all delinquencies are excluded from your CR, you are then categorized as having a "clean" payment history, which places you into a better scoring category, or "bucket." As you have surmised, that can, apart from the individual impact of the derog, produce additional opportunity for overall score improvement.
So, in my opinion, yes, moving to a "pristene' payment history should have its own beneficial future impact.
