Be very careful about using things like grease or non drying paint (I'm pretty sure the use of carpet track and broken glass is now illegal, but don't quote me!) without very explicit warning signs, I'm pretty sure that you could be legitimately sued if someone falls foul of this and you hadn't posted warnings. its all to do with areas of your property that are accessible to the public, either lawfully or unlawfully (trespassing etc) in which they can either be injured or damage their own property!
I would speak with Local Authority and crime prevention bods for sure!
How about a holly or pyracantha (these have 2 inch spikes on them) - I'm growing these along our back fence which backs on to council land. They have berries which the birds eat - (some may even drop over the council fence and start growing from the other side?). There is also a holly which has not only spikes, but spikes growing from the center of the leaves (I took one out in another part of my garden cos it was vicious). I need protective gear to prune all these, but they can be cut back hard if you need to.
Re the rose - we have a 'Wedding Day' white rose, which is a rampant rambler growing over a pergola and again very spiky - but this has to be pruned every year to keep it in check.
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