A good but long route. You need to plan long number of days for in many places you need a break. Also check the cross country entry details for from bhutan you are entering India again. Have a safe journey and all the more best for cycling.
Itz a good plan bro, but in this season it is too difficult to cover ur preffred route, from October ending to May 3rd week many of the routes due to fall of heavy snow and bad weather, so you plan in the month of May last week to August last week, carry ur passport with u for not getting issues at nepal border and butan, it takes average 120 days to cover.