version - 0.7.4
cluster size = 3
RF = 3.
data size on a node ~500G

I want to do some disk maintenance on a cassandra node, so the process that I came up with is
Is this process sane. Never done a read repair on this cluster before, is that a problem? Should I run it per CF? Would it help if I did this before bringing the node down?

Any pointers, things to worry about.