Yes, if you think that the business side (at least making profits is not the main objective) of music is not important at all in this kind of event - the only way is to really organize it yourselves.
Get some metalheads who have some money, pool them together (metalheads + their money) and DIY. The benefits that I can think of (if you manage to pull this together) are -
1) At least the organizers (you metalheads, that is) know what the audience want, since they are passionate about metal themselves.
2) The organizers will know exactly what goes on behind the scene, in terms of what really needs to be done, the steps that need to be taken right from the start to the end, all that planning and final execution.
3) The organizers will eventually come to learn, experience and appreciate the non-music side of organizing a music event - it does take a lot of effort and planning. Not to mention money. If you want to do a good show, that is, and not a half-baked gig that you will forget in three days (I think there are a lot of these nowadays - primarily because it's more about making money than anything else, to the organizers).
IMHO, I think these kind of festivals should start on a more focused tone - restrict one festival/event to either metal or rock (hard rock or pop rock or indie rock or emo rock or pussy rock or whatever) so that people can make a much speedier decision to attend because you don't want them to be confused and have to mull over whether they should come cos there's a large possibility of fat emo kids with thunder thighs turning up in skinny jeans, some with their buttcracks showing if you hold a festival and mix a few metal bands and a few emo bands together.
Well, I foresee that if the metalheads here (at least the mature ones with some money) are really passionate about this idea of organizing a festival themselves - it can still happen, with guidance and professional advice from S.O.F.T, and of course referrals to sponsors (cos a festival to me is quite big - at least 1,000 people attending).
What you guys need is just to start the planning, think and list every single detail about the tasks that need to be done to make this event happen, and take it from there. I am sure there are some business students here who at least know something about event planning, and budgeting and all that shit.
Yes, it is easy to imagine yourselves playing on the stage under the bright lights and having your rockstar moment but there IS a lot of work behind all that to make it happen, at least in a festival setting. The logistic part will probably turn you off - all that technical aspects of sound, the stage that needs to be built, ticketing, crowd control and security, sponsorship, marketing and advertising, performance licensing, contingency planning (in case it rains), presentation (banners, poster etc), host(s) and a lot of other shit. Of course you can tie up with some event planners or venue owners (like The Esplanade, for example) but that will definitely add to the costs considerably.
I think the whole point is - there are a lot of youngsters here in Singapore who are into metal music, and maybe a lot of them are good musicians too who can definitely put up a good show but there may be a lack of their older counterparts who have the money, the maturity, the experience and the level-headedness to guide the youngsters, or at least help organize these types of metal music festivals. Not with the local current emphasis on conventional career paths of being lawyers, doctors, banking professionals and all that. It's just not a popular and profitable path to take in Singapore, being a full-time musician or something like that.