craftgrrl | Earrings and glue

(first time posting):
I've made a couple varieties of earrings for sale. Since they ARE for sale (which is a new development to my crafts): I am trying to clean them up and make them look professional. I'd like to show what I have so far and ask for your help with some problems? My friends think I'm being too picky, but for business I feel like I have to be more careful. Thank you for your help!

the exposed glue seems unprofessional. I haven't found any yet that I expect to be strong enough to hold the non-porous smooth metals to plastic as well as being easy to apply "cleanly" without visible residue once dry. Mostly I'm using "fabri-tac: permanent adhesive." I also bought some "ultimate" polyurethane glue since it was the only kind I could find that specifically mentioned metal and plastic in it's applications, but afterword I read more carefully and found out it expands when it dries. It's on these checked earrings (or at least the left pair, to be sure).

For the flowers I'm trying to figure out ways to cover it:

Most of them have green string glued around the base, but the glue that I used to glue the string in place becomes apparrent as well so I don't like it so much. The one on the far right is painted with tempera paint. That looked pretty good except for a coulple of "holes" which I then filled with glue and have yet to paint over. Presumably now that the hole is full I can paint over it again for a uniform look. Not sure if the tempera paint would wash off if the earrings got really wet though?

I also need help with my dremel. I couldn't figure out how to put on the cutting attatchments. :(

thank you for your help!

EDIT: So MANY nice and helpful comments!! I want to thank you all individually. ^___^ <3