Sounds like you have it under control! What I have found, when I left dead roots and old medium behind, the next time (2-3 years later) when I repotted the now-healthy plant, that I could clean that old stuff, with no harm - because the plant had a chance to grow some new roots. Especially when you pot "out of season" - when it's not producing new roots right away, it pays to be gentle, disturb what it does have as little as possible.