Willer Express & Japan Bus Lines Pass

I am planning a trip around Japan and this time, I will depend solely on buses.
I found these 2 passes in the Willer Express site. I am confused. Greatly appreciate if you can tell me their major differences. Is one inclusive of the other or both are totally different bus Companies ? Beside these 2, are there any other bus pass for long distance travel?
Which are some of their places that can't be reached by train ? I am flexible on my itinerary, so hope to make the best use of it.
Any opinion or information will be greatly appreciated. Thank you.

I wrote to Willer Express before but they didn't reply me.

It is very confusing, indeed.

The routes covered by the Japan Bus Lines Pass are listed here. They include routes by Willer and various other companies:
http://japanbuslines.com/en/buspass/available-routes.html

Meanwhile Willer's Japan Bus Pass only covers the routes directly operated by Willer, as shown listed on the following page:
https://willerexpress.com/st/3/en/pc/buspass/

I didn't know about those passes. I have looked up single tickets for overnight buses like Kyoto - Tokyo and the prices of the bus rides were too expensive to justify the inconvenience of a bus ride.
But those passes seem great. 5 days (non consecutive) for 12 800 Yen.
They seem to have just one huge downside. Almost all of them depart from Tokyo or Osaka/Kyoto. Which means I always have to go back to the starting point. If I want to go from Hakata to Hiroshima I have to take a bus from Hakata to Osaka and than Osaka to Hiroshima. No direct connection Hiroshima-Okayama or Okayama-Himeji. So you need a lot of additional single tickets for those routes to avoid insane detours.

So depending on where you go, it seems to be a little inconvenient but could also be a super cheap way to travel if the available bus routes suit the itinerary.

Thanks Uji,

Do you mean that the JBL pass will include all the Willer Express buses with some other bus line routes? Then I just need to check whether I need those "other lines". If not, I will just go for WE.

I am looking for some off the beaten routes, can you give me some ideas where to visit ?

TomMunich,
Yes, the inconvenience is there aren't as many connections as trains but it covers all the major cities. Hiroshima and Fukuoka is not on the same line but if the connection is on the same day or date, it is counted as one day use, not according to tickets or trips.
I am keen to try it as I have not try long distance bus in Japan before, so that I can report to help other travellers later.

Mr Uji,

I found a bus from the Willer Express website that runs from Tokyo Ikebukuro to Tono Kazeno-Oka by Kakusei Kogyo Bus from Thursday to Sunday. Is this the bus station for Tono and is this bus Company applicable with the Willer Express bus pass ?

Do you mean that the JBL pass will include all the Willer Express buses with some other bus line routes?

I think so, but I haven't actually gone through the list and checked on eby one.

Then I just need to check whether I need those "other lines". If not, I will just go for WE.

I think it easier to go through the list of routes covered by Willer, as there aren't too many of them.

I am looking for some off the beaten routes, can you give me some ideas where to visit ?

Some of the relatively "off-the-beaten" routes by Willer include the line to Matsuyama, Izumo and the Tohoku Region.

Is this the bus station for Tono and is this bus Company applicable with the Willer Express bus pass ?

No. The list of lines covered by the Willer pass can be viewed here. It is not very long:
https://willerexpress.com/st/3/en/pc/buspass/

Mr Uji,
I found the Tono bus from Willer Express bus search on Tokyo to Iwate, from Wikitravel page of Tono.
Lucky I asked. I know that route map of Willer Express only reach the major cities but I thought that map is small and don't show all the smaller places. Do you mean in the WE website, Tono is meant for the Japan Bus Lines Pass? But JBL have its own search page page seen from WE website too.
Now how can I be sure which buses are included or not in the Willer Express Pass.
I also have the question of whether all types of buses and seats are covered in the Pass or not, as I see that some buses are more luxurious than the others.

Hope you can help in any way. In case you are not sure, is it possible for you to email them in Japanese and see what's their reply?