You've got to get your point across. Probably, you're selling something: maybe it's your product or service to the end user; maybe it's your idea to an investor. Whatever you're saying, you have a limited amount of time to get and keep someone's attention, so don't waste that time with words like these. They slow you down and diminish your message.
We know you think so. That's why you're saying it. So say it. This goes for "In my opinion..." as well. Saying those words draws attention to the fact that you're offering an opinion that's up for debate. I find that I use "I think" when I'm trying to soften what I'm saying, and now I'm working actively to take that out of my speaking and, especially, my writing.
This diminishes your point, and there's no need for the word, anyway. "Just a little bit" works fine as "a little bit." More importantly, "I would like to speak with you" is better than "I would just like to speak with you."
It's too casual at best and sexist at worst. There are many other ways to address a group. Try "you all" and "everyone."
If it's not bad, it's good, right? "Not bad" has a negative slant that's unnecessary and not something you want to reinforce in your own mind. If someone asks how you are, say you're doing well — great, even. If you say it enough times, you'll believe it.
We all know that "How are you?" isn't a question that's normally expecting a totally honest answer (unless it's asked by your mother, perhaps). It's small talk, and it can be answered with positive small talk.
Don't ask for confirmation. You already know you're right. And if someone disagrees, they'll tell you so, anyway.
Do you notice any of these words and phrases in your speech and writing?