I would agree with most of that.
Here's some other thoughts in no order:
Work out what it is are trying to do: i.e. put on a regular dnb night, give people a chance to play out, get big names down, etc...
I'd recommend having 1 or 2 nights planned to start, see how it goes and take it from there...
Re: 2 rooms. 1 room is always going to be busier and vibier than the other. Don't try and do too much at first. Try and get your main room working first, you can add a second room later.
Think about what kind of night you want to put on, re: what style of dnb etc, what type of MCs (and how many).
IMO, trouble often goes together with MC heavy nights. Dress codes might put some people off, (specially if it's a venue they don't know, cos it can look uptight) and not especially the ones who'd cause trouble.
I know people in London who are putting on regular free entry nights in 200 ish capacity bars / small clubs. The venue don't charge anything and pay the promoter a % of the bar take. Meaning a promoter can try out / put on a successful small night, get a bit of money back and get a crowd in, and start building the name up. One night I know does dnb on a Tuesday night for free before 10, £3 after. Sometimes they do big names (Andy C & residents) at £5 or 6 all night and keep it ticking along and varied like that.
Consider Student Union venues, if there's anything local. Some might not let not students in, but many do. Good way to do summat cheap.
Venues want paying punters and big bar takes. A full club / free entry bar night is better than a nearly empty £5 a head night. And will get you more dates offered by the venue.
Try to get some residents / regulars together. Hopefully as the night builds up everyone builds up their names.
Think about if / how much people will pay to see local DJs they haven't heard off. Just cos it's a dnb night is only gonna get so many people in, in itself.
I wouldn't worry about lack of experience. Common sense goes a long. New problems happens all the time, that you can't anticipate.
I'll have a think. Gotta rush off now.