Sounds like we're fairly similar. I bought my 620 Dark this year for a little over $5k, registration is about the same as your road tax fee, my insurance is $203 per year and that's about it. Of course we haven't gotten up to $5.50 per gallon for gasoline - yet. That is truly painful. Up here in Northern California it is about the most expensive you'll find in the U.S. at roughly $2.00 per gallon. In the summer it goes up to $2.50-2.75 or so. On the plus side, if gas were that expensive everywhere maybe more people would see the virtues of motorcycles.
It seems your insurance differs like ours does over here. It depends on area, value of the bike and of course age of the rider. If we don't make a claim then we can accumlate no claims discount which can go up to 60% max, once we've got to the max then you can protect your no claims by paying slightly more. Also our policies are either fully comprehensive or third party, fire and theft. The type of bike is taken into consideration eg a 21yr old on a R1 in London would be about $1600 a year so it does pay to an old git would on a monster.
I'm in chicago, 28, single, clean record, with an 03 M800S and pay 600/yr, full coverage. I can't believe I'm saying this, but I can't wait to turn 30 if only to get my auto and bike insurance rates down. my audi is $1,200/year, full coverage. ugh.