there is something i am curious about i remember sakurai stated he didnt Takamaru and Ayumi due to them being japanese exclusive characters but now that its no longer the case why they havent been added yet?
Well, them getting in would probably be via filling a slot explicitly dedicated to an NES-era retro rep, and there didn't seem to be such a slot this time around (likely due to EiH and less unique newcomers in base overall, and them wanting a more recognizable character for the promo bonus slot). It probably takes more than what they've gotten (remakes, rereleases, and cameos) to be seriously viewed as more than one-off-NES-game types.
I don't think being Japan-exclusive was the only reason they weren't in, even if it was the one cited by Sakurai. They're both smaller series even after their Western releases, and even among the one-off NES games, they're still smaller names than the likes that have already been repped (even Ice Climber).
Maybe it was too late for their inclusion with Sakurai.
I mean, characters like these don't exactly get added based on good timing...
But it's possible that the one-off-NES-era types not being so much of a "surprise" anymore is going to make them less likely going forward. They have pretty consistently valued this era highly, though, so they might also continue with it.
If another NES one-off type gets added, I would see Excitebiker as the most glaring omission due to high sales, overall notoriety, and close association with Miyamoto and the making of Super Mario Bros. A good exercise is to sift through Wikipedia's list of best-selling NES games, crossing out all third parties and games/series already repped by PCs in Smash, and then seeing what's left (with the reminder that sales charts should be taken with a grain of salt and aren't the only thing to consider of course).
And yes, I am aware that Excitebike is not technically a one-off but in terms of its chances for Smash it is probably best considered primarily as such.