it's fairly easy to record a demo. if anyone was blatantly hacking (shaking screen, all head shots - the things we've all seen before) a 20 second demo will do and a ban can be made with the proper evidence. But, if it takes an hour of spectating to get proper evidence, then it obviously wasnt as blatant and should be brought up for discussion with the evidence at hand. it seems that numerous rounds were needed for the ban to be made, this imo means that you were personally debating the verdict in your head (sorry if this is a bad assumption). but anyways, if the conclusion is that hard to come across, more opinions are need.
again, i dont think giving anyone power to ban someone with no tangible evidence is a good idea. ive been playing here for almost 4 years and have a good feeling as the how the server should be ran. ive disagreed with bans in the past, but at least they were put up to votes with demos (i.e. sushi).