While Travis Strikes Again: No More Heroes is spin-off, Suda51 definitely has plans for the mainline franchise. As a matter of fact, Suda51 said that he already has an outline for where he would take Travis in the next, official numbered sequel. The thing is, Suda51 needs to drum up some interest in the franchise to actually make that numbered sequel happen, which is where Travis Strikes Again comes in. The success/failure of that title could directly relate to No More Heroes 3 actually happening, or being shelved.
As for Travis Strikes Again, Suda51 had a few more tidbits about the game's development to share.
- game is 35-40% complete
- Suda51 is confident the game will release this year
- you will learn new skills for both Travis and Badman, and those skills will be different for each character
- there will be different types of gameplay
- 2 DJs will handle the music of the game, with Jun Fukada working on sound effects
- Masafumi Takada will probably make new tracks for the game