balancing gels

Eyes are going to reflect the colour cast on them. If you want other parts of the image to show one shade, and getting it there means also throwing the same light into the eyes, then I think your best bet is to fix it in post. Create a new layer, white balance off the eyes, adjust the new colour balance to taste, blend needed parts into original image.

Does anyone have better suggestions?

That makes sense.

Ideally I would like to go for something like this in future

(18+?) http://www.modelmayhem​.com/portfolio/pic/237​31064

Or this (definitely 18+) http://www.modelmayhem​.com/portfolio/pic/106​05858

Bold color but neutrally balanced in the middle. How do they prevent spillage of color ? Balance it out with a normal speedlight for the key light?

Can't see the first one you linked because I don't have an account, but the second one is possibly done by colour balancing to the gel colour itself.

So, you light the room normally, but then you put one flash with a colour filter over it. You shoot onto a white balance card and use this colour light and claim it is 'white'. The camera doesn't really care, it will play long, however everything else that was white is not shifted to another colour. But you are going to shift the 'white' light to either opposite or 1/3 the way around the colour wheel. (I forget exactly how the math works out)

For example picking something that is 'blue' to become your 'white' will make everything that was actually white look yellow. Picking something that was red makes white jump to green, etc. It is easy enough to play around with, and possibly the easiest way to control the colour spill from falling 'onto' the model. In this case you're forcing all the colour onto them in the first place and going from there.

You do have to watch out for colour reproduction with that method however. If you your model wearing orange earrings, and you gel her with a blue light to force everything else to an orange colour, then the earrings are going to fade toward black if they're not getting enough light from other sources. (Because you're not longer lighting them with anything near orange.)

Ohhh good idea...I didn't realize it would be so simple. I can do that.