Clare,
As a relative newbie on the forum (but very long time reader of your prestigious journal) I'd like to throw in my two penn'orth - but do stand ready to be shot down.
Frankly, I do not believe that the format of the printed medium translates well to the format of the electronic medium. You only have to look at the Daily Telegraph as an example. I know that the DT is daily and WHF is monthly but I do think that the principle still stands. The paper copy of the DT is published in a format where you know - physically - where everything that you like about the publication is situated. If you want sport or the letters page your previous experience with the paper tells you exactly where to look. The electronic version of the DT
http://www.telegraph.co.uk/ is vey different, in that everything is categorised according to subject topic (but it took them years and lots of iterations to get to what the publish online today). Every day the front page is formatted the same, but as an online reader it is also very very easy to dive directly to those areas or specialist aspects that interest me most. I have my own favourite aeas of the DT website, just as I do the WHF mag (and the WHF forum), and believe that you would be doing WHF a disservice by trying to replicate onscreen what we see in print.
I fully support your directional idea of online publishing - and potentially increasing your revenue - but as someone who has lived overseas for many years (but now recently back in the UK), I can clearly cast my vote for an online format that is more clearly topic structured and searchable. I read the DT online every day - and still buy it every Saturday - and if WHF were to publish electronically (you're almost there, anyway !) I would still buy the paper copy every month, but would only subscribe to the electronic version if it was NOT a replication of what I see on paper.
Online publishing offers such great flexibility, so think long and hard before you commit yoursef to a format as, if you don't get it right you possibly stand not to gain but to lose.