besides using a lot of lanolin on the leather to keep it soft, there is one change I did that made a big difference. There is a small lip on the door sill plastic cover that was ment to act as a seal, but over time has hardened and now seems to rub on the door. I cut it off with a razor blade on all 4 door openings. It is right under the silver trim and you can't see it here, because I cut it off. But you know where to look now. I got this info from somebody else and would give him credit, but I forgot from whom.
I have not noted any negative effect from this 1mm lip missing.