I remember looking at the job vacancy at MI 6 months ago and do kind of kick myself for not applying (ok realistically I probably wouldn't have got it but one can dream). A new writer couldn't change any site, especially MI, overnight, but given that the interviews are supplied, or they just rewrite news that is already on the wire, change could happen. Cutting out the shit talking and being hard on those commentors would make some difference, but the biggest change one could make is writing proper articles not just extended headlines. If there isn't half a page of words in a story, it's not a story so don't publish it.
Realistically if one could figure out how to get the interviews the rest of the job creating a decent site is not that difficult.