As someone who did way more speedpainting - loose painting work to trying to break into tattoo concepts I can say that I too really struggled at first with strong line work. My designs would constantly get rejected because the linework was not there enough for them. Now that I do more linework I feel it cheapens my speedpainting - so now I almost have to break myself of the strong line-habit.
I think your line work is really awesome! I've always had a light touch and my hand shakes from the stress of trying to perfect the weight of the lines. Delicate line work seems to still be trending but again, it's a waste if it fades. http://vmagazine.com/article/dr-woo-los-angeless-demand-tattoo-artist/
He does real gentle work - very detailed/minimalist in those tattoos. I like it. Most of my old work has very little line work and I often think it looks better then my newer stuff. It could be a shift I am trying in style, and getting into traditional again always seems to come with drawbacks. heh As you can tell I judge my work too much haha.
We all do it. Drives us mad.