I appreciate you coming up with this and putting the effort into writing this all down, I myself have pretty lackluster ideas improving clans even though I personally see them as an important system in expanding the Apb, um, experience and could help with player retainment.
I think that 'clan visibility' isn't too bad in Apb, aka on the scoreboard, so I don't know if I'd want it to be as complicated as showing every detail. Custom color and variations on the brand are good ideas, though.
Some ideas (that come from the few other games I've played that seem to clans well) one is having a system that allows you to have your clan listed on a 'recruitment page' along with the requirements listed out for joining in which a player can apply. Could also be a money sink in order to have your clan on the page, idk.
Having clan items more easily available is a tricky one, having a shared bank is nice, but in some MMOs I've experienced is that they have unrealistic demands on members, e.g. having to deposit a large amount of ingame $ per week into the clan bank. Would need to weigh all the pros and cons of each feature, possibly gaining passive funds (a set percentage of what each one earns playing)
Food for thought is something I've noticed in Apb about clans, there seems to be two types of clans (other than the obvious 'custom title generator') 1. large clans that actively recruit, which were more prominent back in the day and 2. small clans of friends that play missions together and don't actively recruit, would seem pertinent to take both types into consideration when deciding on how to improve clans.
I almost would want to suggest letting people be in more clan than one, but curious what what people would think about that, knowing how toxic Apb is that might be a bad idea (people can get weird about things and start drama, etc)