100% Support.
On the last point though, the "*** Days ago" Is better than the "**/**/**" date as its shorter and to the point. It also allows you to easily see how long they've been there instead of trying to do the math yourself.
I support all of the suggestions, though I believe at least half of them would need engine work (name changes, notes on bans, increased ban list size, date added, basically anything that adds extra information to each ban).
From what I understand, a ban list counter & adding permissions on who can ban/unban wouldn't be too hard to do, and (theoretically) searching/sorting bans would be able to reuse the same code from friends/ignores/friends list, so hopefully wouldn't be that hard.
Another useful thing to have (perhaps instead of notes, if that's too much of an issue) would be naming the person who added a ban to the ban list. Though in a way, if Jagex was able to log clan 'broadcasts' to somewhere more permanent (eg an "adventurer log" for clans), that would give you the name & date at which a ban was added without needing to store anything extra on said ban along with solving a whole heap of other problems (one can only hope...)
Star Find Custodian
Although we have not, luckily, had some of the troubles other clans have encountered, I do support adjustments to the ban list with addition of notes. We are a small tight-knit group and rarely recruit. If we had a way to "white list" some guests who are frequent visitors or who we may consider adding to the clan, the option to close to guests would be alright.