You can do better than this. Don't put multiple feature requests into a single issue. What am I supposed to do with this issue if I implement only one of the three things? I cannot close it and keep it open at the same time. The fact that you couldn't pick a descriptive title for the issue also hints at this being wrong. Please create separate requests for separate features.

That being said, option 2 would make more sense to be addressed by a highpass filter.

Should I leave this as-is(deed is already done, request are out).
Or should I make 3 new issues and have this one nuked?

For option 2,
Highpass does make sense, but it would need to also account for start of sample, IF it starts with considerable DC. Like, when you start recording you typically get a decay from DC level.
So I think manual enveloping accounts for stuff like this and is more versatile.

If sample editing envelopes become a thing for option 1, then option 2 through envelopes is a short step away.
If such enveloping is not feasible in near future, then option 2 through highpass is more feasible(with mentioned caveat).

Option 3 should have been separated indeed. I think I can live with options 1 and 2 being in same issue. You?
Heck, I'll do that right now.

Like, when you start recording you typically get a decay from DC level.
So I think manual enveloping accounts for stuff like this and is more versatile.

That pretty much depends on how the highpass is implemented.