We have a similar location, but with a featherboard fence. We've had a couple of boards broken so far -fairly easy to replace though - and of course graffiti. I'm a little surprised you can't secure the wood somehow, but not really familiar with those panels. Chain link solves graffiti, but they too can pulled around a bit remember. And once they get a bit loose it tends to be a viscous circle and the hole thing ends up sagging. An option might be featherboard? ..or ideally, shoot the little s*ds. But anyway....
Regarding plants; I've looked into this because I wanted fast growing "security plants" behind our featherboard at vulnerable points. The local Police web sites tend to list the 'security plants'. This is what I did: The fastest growing of mine are the large 'climbing' roses. I've got Mme Alfred Carriere, Gregoire Staechelin, Gloire de Dijon - all from crocus.co.uk. (Titchmarsh is linked with them so their kosher). In a year and a half they've grown from about 9 inches to 6 feet (with the odd 9 feet branch) and about 4 feet wide. They're very sharp and thorny. Pyracantha (firethorn) is also supposed to be very fast growing (although mine aren't doing much yet - they're 4-5 feet in the same time but were 3 feet when I got them). They have big sharp thorns and are probably the ultimate in 'attack plants' once established - you'd need a flame thrower to get through a big established bush. Hawthorn grows big and thorny, and is supposed to be fast, but my one has done about the same as the Pyracantha so far. Rosa Rugosa won't grow as tall ultimately as those mentioned, but make good 5-6 ft tall hedges when planted together. They have needle like thorns up the stems, and a couple of mine have grown about 4-5 feet in the same time, but some haven't grown more than a foot or so for some reason. I've recently planted some Berberis (yellow and purple) which are of smaller ultimate size, but quite vicious thorns. Some of these plants are more sensitive than others to to soil conditions etc. (probably my Rogosas and drainage). But the Pyracantha should handle most conditions, and if I remember correctly the Hawthorn too. Roses are fast and attractive, but maybe prone to conditions and disease - I had to cut all the leaves off one because of 'rust' but it just sent out more stems and has recovered.
If you go with the chain link, you could have a combination of the thorny stuff for security and some even faster growing non thorny stuff for privacy.
DaveJ
