Truly as their are so many options, they all are viable... Yet, aren't realistic. T do any of this takes a insurmountable amount of time and truly if it comes to pass you've done more damage than good.
Look, if your conflict with a Royal is serious enough for you to want to ban him, it should be serious enough to warrant the time investment you're talking about, which is far from insurmountable by the way. I have seen several such options used on recalcitrant Dukes to great effect. Yes, there's collateral damage, but guess what? Power struggles are not without cost.
