I'm happy with the amount I post a day. I think if you begin to feel that way on here, you're taking this place way too seriously and need to take a step back and perhaps a little break. Contributing to the forums is for enjoyment and pleasure and as soon as posting feels like a chore, you should take a break. (imo)
As a member I never really obsessed over posting a lot or only posting a little, but I just posted when I wanted to, when I felt like it. I never really felt obligated to create a new topic or reply to a current one. Even now, I don't feel pressured to constantly flood my section with posts. I create and reply to threads when I'm comfortable. That way, I'm not being too harsh on myself and sucking all the enjoyment of my time here and I'm still able to contribute.
td;lr
Quality not quantity.