Which type of handle bars are best for off-road & road use?
The best handlebars for on/off-road MTB use are made of unobtainium:



They offer four hand positions including an acceptable aero tuck. The double bar also acts as a hand-shield. The loop at the front is useful for carrying shopping small distances. The total width is narrow enough to squeeze through gaps in traffic, hands protected so long as not using the bar-end position. You get 2x 'dashboard' for mounting lights etc.

The Scott AT4 was made by the earlier incarnation of 'Scott' and they have no  interest in making them now. The alloy is some last-forever furniture alloy so keep your eyes peeled on ebay for some.