Tyre size 205 requires 16' rim. Why don't you try to uprate current stock size of 185/15 to 195/15, assuming your on 15' now. The extra 10mm at each wheels would definitely provide more grip.

your average consumption of 11.4km/litre is more or less there, whereby mine is around 11.8km/L. However, we have member here that could fetch 14km/l.
mine is due on Dec2014... still waiting new quote~

cover RM70k is more than enough~
insuring high value helps you when the car is declared total lost. They either compensate you based on current used car market value, of certain % off the sum insured; example around 80-88% on the insured value.

i saved my own ass on my previous ride whereby market price was RM43k and i insured RM50k. Upon total lost, i claimed 88% off the sum insured, and it helped me to cover my outstanding balance entirely.

depends on your budget, my friend.

a decent 15's 195 should cost around RM180-280 per pcs, depends on what you want.