More often than not is definitely not a filler. It indicates that something happens more often than it doesn’t happen.
I suppose some people use I for one to mean just I, but it really means, “I think [or do] this, and I’m sure there are other people who agree with me or do the same thing.”
If used correctly, these expressions are not filler.
One of the weirdest filler expressions I’ve ever heard is when some people from England stick “sort of” into their speech but shorten it to “sor”. Then they’ll lengthen it and interrupt themselves with a long “soooooooooor”.
In my part of the US, people use, “You know?” as a filler expression, but they’re not really asking you a question. In the South, where people generally talk more slowly, a lot of people use the whole sentence, “You know what I mean?” as filler. I used to answer this every time, as if they really wanted an answer, but then I realized it was just filler.
A lot of Arabs speaking English use, “Believe me!” as a filler expression. It always sounds to me as if they are afraid I think they’re lying (which I often do, and they often are), but I know it’s just a filler expression transferred from their own language.