It takes 17 hours to reach Kathmandu from Banbasa. On the way you could stop by Shuklaphanta national park, sivapur some temples are popular to visit, Banke national park, Kapilvastu, Devghat and stop at Kathmandu. Suppose you are taking almora route then you could stop at Dehradun, Haridwar and joshimath before entering Kathmandu. Road condition is good for winter season is yet to start.
Yes it is possible for sunauli comes under 10 exit points, but do the exit before sunset for the border is considered dangerous after dark. Carry required documents for border checking.